Cellular cassettes for the collection, storage, and analysis of biological samples

ABSTRACT

Disclosed herein are cellular cassettes for the storage, collection, and analysis of biological samples. The cellular cassette can enable easy sample collection and sealing of microwell arrays with semi-permeable membrane for stable storage and future processing of single cells. Also disclosed herein are systems and kits comprising one or more described cassettes. The described cassettes, systems, and kits can be used to create barcoded, single-cell sequencing libraries. Further described herein are methods of using the cassettes, systems, and kits.

CROSS-REFERENCE OF RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.17/314,507, filed May 7, 2021, which is a continuation of InternationalApplication No. PCT/US2020/036197, filed Jun. 4, 2020, which claimsbenefit of U.S. Provisional Patent Application No. 62/858,773, filedJun. 7, 2019, each of which is entirely incorporated herein by referencein its entirety.

BACKGROUND

Cell-based assays with single cell solution has drawn substantialinterest due to the heterogeneity of gene expression. Accessing thedifferences in gene expression among individual cells can facilitate theidentification of rare cell populations, which cannot be detected byanalyzing pooled cells. The isolation and analysis of single cells canbe performed in droplets-based platforms such as the Chromium Systemsold by 10× Genomics. Using the Chromium System, reactions arepartitioned into nanoliter-scale droplets containing uniquely barcodedbeads named GEMs (Gel Bead-in Emulsion). This technology can be used topartition single cells. The isolation and analysis of single cells canalso be performed in microarray-based platforms such as Fluidigm Cl soldby Fluidigm and Seq-well described in US 20190144936A1.

However, the existing technologies fail to provide a solution thatenables efficient asynchronous single-cell analysis. It is challengingto collect and store single cell samples prior to the creation ofsingle-cell sequencing libraries using the existing droplets-based ormicroarray-based systems. Thus, there remains a need for devices andmethods that facilitate the collection and storage of single cells priorto the creation of single-cell sequencing libraries. There remains aneed for devices and methods that facilitate asynchronous single-cellanalysis.

SUMMARY

Described herein are devices, systems, and methods for collecting,storing, or analyzing biological samples. The described devices, systemsand methods offer significant advantages over existing technologies; forexample, the herein-disclosed devices, systems and methods enable thecollection and storage of biological samples for asynchronoussingle-cell analysis, and they enable scalable and cost-effectivesingle-cell interrogation of samples, with the efficiency and quality ofcentralized analytical processing. As disclosed herein, biologicalsamples can be captured in any settings including point-of-carelocations. After the biological samples are captured, the biologicalstate and biological information of the samples can be locked-in andpreserved, and the integrity of the samples can be maintained as long asneeded during storage, shipping, and eventual processing. In addition,the captured samples can be processed centrally, which improvesefficiencies and reduces variabilities.

In one aspect, disclosed herein is a cassette for collecting, storing,or analyzing bioparticles, said cassette comprises: (a) a plungerassembly that comprises a plunger, wherein said plunger has a bottomsurface; (b) a membrane assembly that comprises: (i) a semi-permeablemembrane that comprises a membrane top surface and a membrane bottomsurface, and (ii) a membrane frame configured to attach to said plunger,wherein said semi-permeable membrane is attached to said membrane frame,and wherein said membrane assembly is configured such that at least aportion of said bottom surface of said plunger is in contact with saidmembrane top surface when said membrane frame is attached to saidplunger assembly; and (c) a loading assembly that comprises a microwellarray and a base that supports the microwell array, wherein saidmicrowell array comprises a top surface that comprises a plurality ofmicrowells displaced therein, wherein said loading assembly isconfigured such that at least a portion of said top surface of saidmicrowell array is in contact with said membrane bottom surface whensaid membrane assembly is attached to the loading assembly, and whereinsaid contact between said membrane bottom surface and said top surfaceof said microwell array is configured to retain one or more bioparticlesin said microwell array. In one aspect, disclosed herein is a cassettefor collecting, storing, or analyzing bioparticles, said cassettecomprises: (a) a plunger that comprises a top surface and a bottomsurface; (b) a membrane assembly that comprises: (i) a semi-permeablemembrane that comprises a membrane top surface and a membrane bottomsurface, and (ii) a membrane frame configured to attach to said plunger,wherein said semi-permeable membrane is attached to said membrane frame,and wherein said membrane assembly is configured to allow at least aportion of said bottom surface of said plunger to be in contact withsaid membrane top surface when said membrane frame is attached to saidplunger; (c) a loading assembly that comprises a base and a microwellarray, wherein said microwell array comprises a top surface and aplurality of microwells, wherein said loading assembly is configured toallow at least a portion of said top surface of said microwell array tobe in contact with said membrane bottom surface, and wherein saidcontact is capable of retaining one or more bioparticles in saidmicrowell array. In some embodiments, the cassette comprises a lockingmechanism that is capable of locking the plunger and the membraneassembly in place with the loading assembly. In some embodiments, thecassette comprises a locking mechanism that is configured to lock saidplunger assembly and said membrane assembly in place with said loadingassembly. In some embodiments, the locking mechanism is configured tomaintain said contact between said top surface of said microwell arrayand said membrane bottom surface. In some embodiments, the plungerassembly comprises a top locking member. In some embodiments, theplunger comprises a top locking member. In some embodiments, the basecomprises a bottom locking member that is configured to engage the toplocking member. In some embodiments, the bottom locking member isconfigured to engage the top locking member through a snap trapmechanism. In some embodiments, the contact between the top surface ofthe microwell array and the membrane bottom surface is maintained byengaging the top locking member and the bottom locking member. In someembodiments, the bottom surface of the plunger comprises a curvedsurface. In some embodiments, the bottom surface of the plungercomprises a convex surface. In some embodiments, the bottom surface ofthe plunger comprises an elastomeric surface. In some embodiments, thebottom surface of the plunger is substantially circular. In someembodiments, the said plunger comprises a side surface that comprisesone or more cutouts. In some embodiments, the one or more cutouts aregroves that runs vertically on the plunger. In some embodiments, theplunger assembly comprises a rigid top surface. In some embodiments, theplunger assembly comprises a top surface that comprises a mechanism,through which the position of the plunger assembly or the cassette canbe set or manipulated. In some embodiments, the mechanism on the topsurface of the plunger assembly comprises a handle. In some embodiments,the top surface of the plunger comprises a rigid surface. In someembodiments, the top surface of the plunger comprises a handle. In someembodiments, the semi-permeable membrane has an average pore diameter ofat least 1 nm, at least 10 nm, at least 20 nm, at least 30 nm, at least40 nm, at least 50 nm, at least 75 nm, at least 100 nm, at least 200 nm,at least 300 nm, at least 400 nm, at least 500 nm, at least 600 nm, atleast 700 nm, at least 800 nm, at least 900 nm, or at least 1000 nm. Insome embodiments, the semi-permeable membrane has an average porediameter of at most 20 nm, at most 30 nm, at most 40 nm, at most 50 nm,at most 75 nm, at most 100 nm, at most 200 nm, at most 300 nm, at most400 nm, at most 500 nm, at most 600 nm, at most 700 nm, at most 800 nm,at most 900 nm, at most 1 μm, at most 2 μm, at most 3 μm, at most 5 μm,or at most 10 μm. In some embodiments, the semi-permeable membrane hasan average pore diameter of from about 1 nm to about 200 nm. In someembodiments, the semi-permeable membrane is configured to retain one ormore beads, one or more bioparticles, or both. In some embodiments, thebioparticles comprise a cell, a genome, a nucleic acid, a virus, anucleus, a protein, a peptide, or a combination thereof. In someembodiments, the bioparticles comprise one or more cells. In someembodiments, the one or more cells comprise a bacteria cell, a plantcell, an animal cell, or a combination thereof. In some embodiments, theone or more cells comprise a mammalian cell. In some embodiments, theone or more cells comprise a blood cell. In some embodiments, themembrane assembly has a substantially circular shape. In someembodiments, the membrane frame is configured to reversibly attach tothe plunger. In some embodiments, the membrane frame is configured toreversibly attach to said plunger or to said plunger assembly. In someembodiments, the membrane frame is rigid. In some embodiments, themembrane frame comprises a cylindrical shape. In some embodiments, theat least a portion of said bottom surface of said plunger is in directcontact with said membrane top surface when said membrane frame isattached to said plunger assembly. In some embodiments, when saidmembrane frame is attached to said plunger assembly, said at least aportion of the bottom surface of the plunger is in contact with saidmembrane top surface through a medium, which is situated between saidsemi-permeable membrane and said plunger. In some embodiments, themedium comprises an adsorbent material. In some embodiments, theadsorbent material comprises paper or superabsorbent polymers. In someembodiments, the medium comprises cell preservation solution. In someembodiments, the medium functions as a reservoir for solution. In someembodiments, the medium functions as a fluid reservoir. In someembodiments, the membrane assembly is configured to allow the bottomsurface of the plunger to be in contact with the membrane top surfacewhen the membrane frame is attached to the plunger. In some embodiments,the membrane assembly is pre-attached to the plunger. In someembodiments, the membrane assembly is pre-attached to the plungerassembly. In some embodiments, the membrane assembly is configured toreversibly attach to the loading assembly. In some embodiments, membranebottom surface comprises one or more reactive functional groups. In someembodiments, the reactive functional groups comprise an amine, anaminosilane, a thiosilane, a methacrylate silane, a poly(allylamine), amaleimide, a 2-iminothiolane, a functional group derived frompolyacrylic acid or bisepoxy-PEG, or a combination thereof. In some casethe top surface of the microwell array comprises one or more reactivefunctional groups. In some embodiments, the reactive functional groupscomprise an amine, an aminosilane, a thiosilane, a methacrylate silane,a poly(allylamine), poly(lysine), BSA, epoxide silane, chitosan,2-iminothiolane, a functional group derived from polyacrylic acid,bisepoxy-PEG, or oxidized agarose, or a combination thereof. In someembodiments, the microwell array comprises one or more cut outs. In someembodiments, the one or more cut outs comprise a cut out located at thecenter of the array, a cut out located on the side of the array, orboth. In some embodiments, the microwell array comprises from about 5000to about 1,000,000 microwells. In some embodiments, the microwell arraycomprises from about 50,000 to about 150,000 microwells. In someembodiments, the average diameter of the microwells on the top surfaceis at least 5 microns, at least 7 microns, at least 10 microns, at least20 microns, at least 30 microns, at least 45 microns, at least 50microns, or at least 100 microns. In some embodiments, the averagediameter of the microwells on the top surface is at most 1000 microns,at most 500 microns, at most 400 microns, at most 300 microns, at most200 microns, at most 100 microns, at most 75 microns, at most 50microns, at most 40 microns, at most 30 microns, at most 20 microns, atmost 10 microns, or at most 5 microns. In some embodiments, the averagediameter of the microwells on the top surface is from about 5 microns toabout 50 microns. In some embodiments, the loading assembly comprises anelevated loading ring surrounding the microwell array. In someembodiments, the loading ring comprises a hydrophobic inward-facingsurface. In some embodiments, the loading ring is part of the base. Insome embodiments, the loading ring is reversibly attachable to the base.In some embodiments, the loading ring comprises a lid that covers themicrowell array. In some embodiments, the loading assembly comprises alid that covers the microwell array. In some embodiments, the lidcomprises one or more openings. In some embodiments, the loading ring isconfigured to retain fluid on the microwell array. In some embodiments,the loading ring is configured to retain from about 0.1 ml to about 5 mlfluid. In some embodiments, the base comprises a recessed area relativeto the microwell array. In some embodiments, the recessed area iscapable of accommodating the fluid retained by the loading ring. In someembodiments, the recessed area is configured to accommodate the fluidretained by said loading ring. In some embodiments, the base comprisesone or more ports configured to allow liquid removal. In someembodiments, the one or more ports are situated on the side of the base.In some embodiments, the one or more ports are situated on the bottom ofthe base. In some embodiments, the base comprises one or more channelsthat are capable of facilitating a fluid flow from the recessed area tothe one or more ports. In some embodiments, the base comprises one ormore channels that are configured to facilitate a fluid flow from saidrecessed area to said one or more ports. In some embodiments, theloading assembly is configured to allow the top surface of the microwellarray to be in contact with the membrane bottom surface, thereby sealingthe microwell array. In some embodiments, the base comprises one or morekey holes configured to allow an insert of one or more keys, wherein theinsert of one or more keys disengages the top locking member and thebottom locking member. In some embodiments, the insert releases theplunger from the loading assembly and the membrane assembly. In someembodiments, the insert releases said plunger assembly from said loadingassembly. In some embodiments, the microwell array comprises a pluralityof beads. In some embodiments, at least 80%, 85%, 90%, 95%, 99%, 99.9%,or 100% of the microwells contain a single bead. In some embodiments,one or more of the plurality of microwells comprise a single bead. Inone aspect, disclosed herein is a cassette for collecting, storing, oranalyzing bioparticles, said cassette comprises: (a) a membrane assemblythat comprises a membrane frame and a semi-permeable membrane attachedto said membrane frame, wherein said semi-permeable membrane comprises amembrane top surface and a membrane bottom surface, wherein at least aportion of said membrane top surface and membrane bottom surface areunsupported by any substrate; and (b) a loading assembly that comprisesa base and a microwell array, wherein said microwell array comprises atop surface and a plurality of microwells, wherein said membraneassembly is reversibly attachable to said loading assembly, and whensaid membrane assembly is attached to said loading assembly, saidmembrane bottom surface is in contact with said top surface of saidmicrowell arrays. In one aspect, disclosed herein cassette forcollecting, storing, or analyzing bioparticles, said cassette comprises:(a) a membrane assembly that comprises a membrane frame and asemi-permeable membrane attached to said membrane frame, wherein saidsemi-permeable membrane comprises a membrane top surface and a membranebottom surface, wherein at least a portion of said membrane top surfaceand membrane bottom surface are unsupported by any substrate; and (b) aloading assembly that comprises a base and a microwell, wherein saidmembrane assembly is reversibly attachable to said loading assembly, andwhen said membrane assembly is attached to said loading assembly, saidmembrane bottom surface is in contact with said microwell. In someembodiments, the contact between the membrane bottom surface and the topsurface of the microwell is configured to retain one or more beads, oneor more bioparticles, or both. In one aspect, disclosed herein is acassette for collecting, storing, or analyzing bioparticles, saidcassette comprises: (a) a membrane assembly that comprises a membraneframe and a semi-permeable membrane, wherein said semi-permeablemembrane comprises a membrane top surface and a membrane bottom surface,wherein at least a portion of said membrane top surface and membranebottom surface are unsupported by any substrate; and (b) a loadingassembly that comprises a base and a microwell array, wherein saidmicrowell array comprises a top surface and a plurality of microwells,and wherein said membrane bottom surface is configured to bond with atleast a portion of said top surface of said loading assembly. In oneaspect, disclosed herein is a cassette for collecting, storing, oranalyzing bioparticles, said cassette comprises: (a) a semi-permeablemembrane that comprises a membrane top surface and a membrane bottomsurface, wherein at least a portion of said membrane top surface andmembrane bottom surface are unsupported by any substrate; and (b) aloading assembly that comprises a base and a microwell array, whereinsaid microwell array comprises a top surface and a plurality ofmicrowells, and wherein said membrane bottom surface is configured tobond with at least a portion of said top surface of said loadingassembly. In some embodiments, (i) the membrane bottom surface, (ii) thetop surface of the loading assembly, or both comprise one or morereactive functional groups. In some embodiments, the membrane topsurface and the membrane bottom surface are unsupported by anysubstrate. In some embodiments, the cassette comprises a plungerassembly that comprises a plunger, and wherein the plunger assembly isreversibly attachable to said membrane assembly. In some embodiments,the plunger is in contact with said membrane top surface when saidplunger assembly is attached to said membrane assembly. In someembodiments, the plunger contacts said membrane top surface directly orthrough a fluid reservoir. In one aspect, disclosed herein is a cassettefor collecting, storing, or analyzing bioparticles, said cassettecomprises: (a) a semi-permeable membrane that comprises a membrane topsurface and a membrane bottom surface, and (b) a loading assembly thatcomprises a base and a microwell array, wherein said microwell arraycomprises a top surface and a plurality of microwells, wherein saidsemi-permeable membrane is configured to bond to at least a portion ofsaid top surface of said microwell array. In one aspect, disclosedherein is a cassette for collecting, storing, or analyzing bioparticles,said cassette comprises: (a) a semi-permeable membrane that comprises amembrane top surface and a membrane bottom surface, and (b) a loadingassembly that comprises a base and a top surface that comprises amicrowell displaced therein, wherein said semi-permeable membrane isconfigured to bond to at least a portion of said top surface. In oneaspect, disclosed herein is a cassette for collecting, storing, oranalyzing bioparticles, said cassette comprises: (a) a semi-permeablemembrane that comprises a membrane top surface and a membrane bottomsurface, and (b) a loading assembly that comprises a base and amicrowell array, wherein said microwell array comprises a top surfaceand a plurality of microwells, wherein said semi-permeable membrane isconfigured to bond to at least a portion of said top surface of saidmicrowell array, and wherein said bonding does not require a heatingprocess. In some embodiments, the bonding between the membrane bottomsurface and the microwell array retains one or more bioparticles in saidmicrowells. In some embodiments, the membrane bottom surface isconfigured to bond with at least a portion of the top surface of saidloading assembly under a temperature of below 50° C., 45° C., 40° C.,35° C., or 30° C. In some embodiments, the membrane bottom surface isconfigured to bond with at least a portion of the top surface of saidloading assembly under ambient temperature. In some embodiments, thebonding is reversible. In some embodiments, the membrane bottom surfaceis configured to bond with at least a portion of said top surface of themicrowell array at a temperature of below 50° C., 45° C., 40° C., 35°C., or 30° C. In some embodiments, the membrane bottom surface isconfigured to bond with at least a portion of said top surface of themicrowell array under ambient temperature.

In one aspect, disclosed herein is a cassette for collecting, storing,or analyzing bioparticles, said cassette comprises, from top to bottom:(a) a plunger assembly that comprises a top surface, a plunger, and atop locking member, wherein said plunger comprises a bottom surface; (b)a membrane assembly that comprises: (i) a semi-permeable membrane thatcomprises a membrane top surface and a membrane bottom surface, and (ii)a membrane frame configured to reversibly attach to said plungerassembly, wherein said semi-permeable membrane is attached to saidmembrane frame, and wherein said membrane assembly is configured toallow at least a portion of said bottom surface of said plunger to be incontact with said membrane top surface when said membrane frame isattached to said plunger assembly; and (c) a loading assembly thatcomprises: (i) a base that comprises a bottom locking member, and (ii) amicrowell array situated on said base, wherein said microwell arraycomprises a top surface and a plurality of microwells, wherein saidbottom locking member is configured to engage with said top lockingmember, thereby maintaining a contact between at least a portion of saidmembrane bottom surface and at least a portion of said top surface ofsaid microwell array. In one aspect, disclosed herein is a cassette forcollecting, storing, or analyzing bioparticles, said cassette comprises,from top to bottom: (a) a plunger assembly that comprises a top surface,a plunger, and a top locking member, wherein said plunger comprises abottom surface; (b) a membrane assembly that comprises: (i) asemi-permeable membrane that comprises a membrane top surface and amembrane bottom surface, and (ii) a membrane frame that holds saidsemi-permeable membrane, wherein said membrane frame is attached to saidplunger assembly, wherein said bottom surface of the plunger is incontact with said membrane top surface; and (c) a loading assembly thatcomprises: (i) a base that comprises a bottom locking member, and (ii) amicrowell array situated on said base, wherein said microwell arraycomprises a top surface and a plurality of microwells, wherein saidbottom locking member is configured to engage with said top lockingmember, thereby maintaining a contact between at least a portion of saidmembrane bottom surface and at least a portion of said top surface ofsaid microwell array. In one aspect, disclosed herein is a cassette forcollecting, storing, or analyzing bioparticles, said cassette comprises,from top to bottom: (a) a plunger assembly that comprises a top surface,a plunger, and a top locking member, wherein said plunger comprises abottom surface; (b) a membrane assembly that comprises: (i) asemi-permeable membrane that comprises a membrane top surface and amembrane bottom surface, and (ii) a membrane frame configured toreversibly attach to said plunger assembly, wherein said semi-permeablemembrane is attached to said membrane frame, and wherein said membraneassembly is configured to allow at least a portion of said bottomsurface of said plunger to be in contact with said membrane top surfacewhen said membrane frame is attached to said plunger assembly; and (iii)a bottom locking member that is configured to engage with said toplocking member; and (c) a loading assembly that comprises a microwellarray situated on a base, wherein said microwell array comprises a topsurface and a plurality of microwells. In one aspect, disclosed hereinis a cassette for collecting, storing, or analyzing bioparticles, saidcassette comprises, from top to bottom: (a) a plunger assembly thatcomprises a top surface, a plunger, and a top locking member, whereinsaid plunger comprises a bottom surface; (b) a membrane assembly thatcomprises: (i) a semi-permeable membrane that comprises a membrane topsurface and a membrane bottom surface, and (ii) a membrane frame thatholds said semi-permeable membrane, wherein said membrane frame isattached to said plunger assembly, wherein said bottom surface of theplunger is in contact with said membrane top surface; and (i) a bottomlocking member that is configured to engage with said top lockingmember; and (ii) a loading assembly that comprises a microwell arraysituated on a base, wherein said microwell array comprises a top surfaceand a plurality of microwells. In some embodiments, the bottom surfaceof the plunger is in contact with said membrane top surface through afluid reservoir that comprises an adsorbent material and a cellpreservation solution. In some embodiments, the base comprises one ormore ports for fluid collection. In one aspect, disclosed herein is acassette for collecting, storing, or analyzing bioparticles, saidcassette comprises, from top to bottom: (a) a plunger assembly thatcomprises a top surface, a plunger, and a top locking member, whereinsaid plunger comprises a bottom surface; (b) a membrane assembly thatcomprises: a semi-permeable membrane that comprises a membrane topsurface and a membrane bottom surface, and a membrane frame configuredto reversibly attach to said plunger assembly, wherein saidsemi-permeable membrane is attached to said membrane frame, and whereinsaid membrane assembly is configured to allow at least a portion of saidbottom surface of said plunger to be in contact with said membrane topsurface when said membrane frame is attached to said plunger assembly;and (c) a loading assembly that comprises: a base that comprises abottom locking member and one or more ports for fluid collection, and amicrowell array bonded to said base, wherein said microwell arraycomprises a top surface and a plurality of microwells, wherein saidbottom locking member is configured to engage with said top lockingmember, thereby maintaining a contact between at least a portion of saidmembrane bottom surface and at least a portion of said top surface ofsaid microwell array. In one aspect, disclosed herein is a cassette forcollecting, storing, or analyzing bioparticles, said cassette comprises,from top to bottom: (a) a plunger assembly that comprises a top surface,a plunger, and a top locking member, wherein said plunger comprises abottom surface; (b) a membrane assembly that comprises: a semi-permeablemembrane that comprises a membrane top surface and a membrane bottomsurface, and a membrane frame that holds said semi-permeable membrane,wherein said membrane frame is attached to said plunger assembly,wherein said bottom surface of the plunger is in contact with saidmembrane top surface; and (c) a loading assembly that comprises: a basethat comprises a bottom locking member and one or more ports for fluidcollection, and a microwell array bonded to said base, wherein saidmicrowell array comprises a top surface and a plurality of microwells,wherein said bottom locking member is configured to engage with said toplocking member, thereby maintaining a contact between at least a portionof said membrane bottom surface and at least a portion of said topsurface of said microwell array. In some embodiments, the bottom surfaceof the plunger is in contact with said membrane top surface through afluid reservoir that comprises an adsorbent material and a cellpreservation solution. In some embodiments, at least one of saidmicrowells comprises a single bioparticle. In some embodiments, thecassette comprises at least 1000 microwells that each comprises a singlebioparticle. In some embodiments, the single bioparticle is a singlecell or a single bead. In one aspect, disclosed herein is a cassette forcollecting, storing, or analyzing bioparticles, said cassette comprises:(a) a plunger that comprises a top surface, a bottom surface, and a toplocking member; (b) a membrane assembly that comprises: (i) asemi-permeable membrane that comprises a membrane top surface and amembrane bottom surface, and (ii) a membrane frame configured toreversibly attach to said plunger, wherein said semi-permeable membraneis attached to said membrane frame, and wherein said membrane assemblyis configured to allow at least a portion of said bottom surface of saidplunger to be in contact with said membrane top surface when saidmembrane frame is attached to said plunger; (b) a loading assembly thatcomprises: (i) a base that comprises a bottom locking member and one ormore ports, and (ii) a microwell array bonded to said base, wherein saidmicrowell array comprises a top surface and a plurality of microwells,wherein said bottom locking member is configured to engage with said toplocking member, thereby maintaining a contact between at least a portionof said membrane bottom surface and at least a portion of said topsurface of said microwell array, and wherein said one or more ports areconfigured to allow liquid removal when said top locking member isengaged with said bottom locking member.

In one aspect, disclosed herein is a system for collecting, storing, oranalyzing bioparticles, said system comprises: (a) one or more describedcassettes; and (b) a cassette frame configured to hold said one or morecassettes. In some embodiments, the cassette frame is configuredaccording to Society for Biomolecular Screening (SBS) standard. In someembodiments, the system comprises from 1 to about 300 of said cassettes.In some embodiments, the system comprises about 6, about 8, about 12,about 24, about 96, or about 120 of said cassettes. In some embodiments,the system comprises one or more keys that are configured such that whenthe keys are inserted to said cassettes, one or more plunger assembliesare released from one or more loading assemblies. In some embodiments,the keys are built into said cassette frame. In some embodiments, atleast two of said one or more cassettes are pre-connected. In someembodiments, the system comprises one or more bioparticle collectionunits. In some embodiments, the collection units comprise one or morecollection plates that each comprises a plurality of recesses. In someembodiments, the collection units comprise one or more conically-shapedcassette collectors. In some embodiments, the cassette collectorscomprise an opening at the center that is configured to allow beads topass through. In one aspect, disclosed herein is a system forcollecting, storing, or analyzing bioparticles, said system comprises:two or more cassettes, wherein each of said cassettes comprises (a) amembrane assembly that comprises a semi-permeable membrane, and (b) aloading assembly that comprises a base and a microwell array, whereinsaid microwell array comprises a top surface and a plurality ofmicrowells, wherein said semi-permeable membrane is configured tocontact at least a portion of said top surface of the microwell arraywhen said membrane assembly is attached to said loading assembly, andwherein said membrane assemblies in at least two of the two or morecassettes are configured to be attached to or released from saidmicrowell array simultaneously. In one aspect, disclosed herein is asystem for collecting, storing, or analyzing bioparticles, said systemcomprises: two or more cassettes, wherein each of said cassettescomprises (a) a membrane assembly that comprises an impermeablemembrane, and (b) a loading assembly that comprises a base and amicrowell array, wherein said microwell array comprises a plurality ofmicrowells that each comprises a bottom surface and an opening at thetop, and wherein said bottom surface of the microwells comprises asemi-permeable membrane, wherein said impermeable membrane is configuredto seal at least one of said openings at the top of said microwells whensaid membrane assembly is attached to said loading assembly, and whereinsaid membrane assemblies in at least two of the two or more cassettesare configured to be attached to or released from said microwell arraysimultaneously. In another aspect, disclosed herein is a system forcollecting, storing, or analyzing bioparticles, said system comprises:(a) one or more cassettes as described herein; (b) one or more keys thatare capable of releasing said plunger from said loading assembly; and(c) a Society for Biomolecular Screening (SBS) standard-sized frameconfigured to hold said one or more cassettes. In some embodiments, thesystem comprises from 1 to about 300 of the cassettes. In someembodiments, the system comprises about 6, about 8, about 12, about 24,about 96, or about 120 of the cassettes. In some embodiments, the keysare built into the SBS frame. In some embodiments, at least two of theone or more cassettes are pre-connected. In some embodiments, the systemcomprises one or more bioparticles collection units. In someembodiments, the collection units comprise one or more collection platesthat each comprises a plurality of recesses. In some embodiments, thecollection units comprise one or more conically-shaped cassettecollectors. In some embodiments, the cassette collectors comprise a holeat the center that allows beads to pass through. In one aspect,disclosed herein is a system for collecting, storing, or analyzingbioparticles, said system comprises: two or more cassettes, wherein eachof said cassettes comprises (a) a semi-permeable membrane, and (b) aloading assembly that comprises a base and a microwell array, whereinsaid microwell array comprises a top surface and a plurality ofmicrowells, wherein said semi-permeable membrane in at least two of thetwo or more cassettes are configured to be attached to or released fromsaid microwell array simultaneously.

In another aspect disclosed herein is a kit for collecting, storing, oranalyzing bioparticles, the kit comprises: one or more cassettes asdisclosed herein, or a system as disclosed herein; and one or morereagents. In some embodiments, the beads are pre-loaded into themicrowells. In some embodiments, the one or more reagents comprise awetting solution, a wash fluid, a lysis buffer, a fixative, a tissuestorage reagent, a cell culture media, or a combination thereof. In someembodiments, a device can comprise one or more cells. In someembodiments, a device can comprise one or more nucleic acids. In someembodiments, the kit comprises instructions that provide a protocol ofusing said one or more cassettes or said system.

In another aspect, disclosed herein is a method for collecting, storing,or analyzing bioparticles using a cassette of as disclosed herein, asystem as disclosed herein, or a kit as disclosed herein. In one aspect,disclosed herein is a method for collecting, storing, or analyzingbioparticles using a cellular cassette, wherein said cellular cassettecomprises: (a) a plunger assembly that comprises a plunger; (b) amembrane assembly that comprises a membrane frame and a membrane thatcomprises a membrane top surface and a membrane bottom surface; and (c)a loading assembly that comprises a base and a microwell array situatedon the base, wherein said microwell array comprises a top surface and aplurality of microwells; wherein said method comprising: loading asample fluid that comprises one or more bioparticles onto said microwellarray, thereby loading at least one bioparticle into one of saidmicrowells; applying said membrane assembly onto said microwell array,wherein said membrane assembly is attached to said plunger assembly; andcontacting at least a portion of said top surface of said microwellarray with at least a portion of said membrane bottom surface, andwherein said contact retains at least one bioparticle in one of saidmicrowells. In some embodiments, the applying and contacting occursimultaneously. In some embodiments, the membrane is semi-permeable. Insome embodiments, each of said plurality of microwells comprises anopening at the top and a bottom surface, wherein the bottom surfacecomprises semi-permeable membrane. In another aspect, disclosed hereinis a method for collecting, storing, or analyzing bioparticles using acellular cassette, the method comprising: loading a sample fluid thatcomprises one or more bioparticles onto a microwell array that issituated on a base, wherein the microwell array comprises a top surfaceand a plurality of microwells, thereby loading at least one bioparticlesinto one of the microwells; applying a membrane assembly onto themicrowell array, wherein the membrane assembly is attached a plunger,and wherein the membrane assembly comprises a membrane frame and asemi-permeable membrane that comprises a membrane top surface and amembrane bottom surface; and contacting at least a portion of the topsurface of the microwell array with at least a portion of the membranebottom surface, and wherein the contact retains the at least onebioparticles in one of the microwells. In some embodiments, the methodcomprises attaching an elevated loading ring that surrounds themicrowell array before the sample fluid is loaded. In some embodiments,the method comprises wetting the microwell array before the sample fluidis loaded. In some embodiments, the wetting comprises loading a wettingsolution onto the microwell array. In some embodiments, the wettingfurther comprises removing the wetting solution from the microwellarray. In some embodiments, the wetting comprises washing the microwellarray with a wash buffer. In some embodiments, the wetting comprisesloading a wash buffer onto the microwell array and leaving the buffer onthe microwell array for about 30 minutes to about 24 hours. In someembodiments, the wetting further comprises removing the wash buffer. Insome embodiments, the sample fluid is loaded by pipetting. In someembodiments, the method further comprises agitating the loaded samplefluid. In some embodiments, the method further comprises incubating theloaded sample fluid. In some embodiments, a ratio of the number ofbioparticles in the sample fluid to the number of microwells in themicrowell array is from about 1:100 to about 1:1. In some embodiments,the ratio of the number of bioparticles in the sample fluid to thenumber of microwells in the microwell array is from about 1:20 to about1:4. In some embodiments, at least 50%, at least 60%, at least 70%, atleast 80%, at least 90%, at least 91%, at least 92%, at least 93%, atleast 94%, at least 95%, at least 96%, at least 97%, at least 99%, or atleast 99% of the bioparticles in the sample fluid are loaded in themicrowells. In some embodiments, the method further comprises applying astorage buffer to the microwell array after the sample fluid is loaded.In some embodiments, the method comprises removing the loading ringafter the sample fluid is loaded. In some embodiments, the membraneassembly is reversibly attached to the plunger. In some embodiments, theplunger comprises a top surface and a bottom surface, and wherein atleast a portion of the plunger bottom surface contacts the membrane topsurface. In some embodiments, the at least a portion of said plungerbottom surface contacts said membrane top surface directly or through amedium. In some embodiments, the medium comprises a layer of adsorbentmaterial and a cell preservation solution. In some embodiments, theplunger bottom surface comprises a curved surface. In some embodiments,the membrane assembly is applied to the microwell array by manipulatingthe plunger. In some embodiments, at least a fraction of fluid isdisplaced after the membrane assembly is applied to the microwell array.In some embodiments, the displaced fluid comprises a fraction of thesample fluid, a fraction of the wetting solution, a fraction of the washbuffer, a fraction of the storage buffer, or a combination thereof. Insome embodiments, the displaced fluid is removed from one or more portslocated on the side of the base. In some embodiments, the contactbetween the top surface of the microwell array and the membrane bottomsurface retains at least 1000 bioparticles in said microwells. In someembodiments, the method further comprises storing the retained at leastone bioparticle for one or more days. In some embodiments, the methodcomprises releasing the plunger from the membrane assembly, therebyexposing the membrane top surface. In some embodiments, the bioparticlesare beads that comprise biomaterials. In some embodiments, thebioparticles are mammalian cells. In some embodiments, the microwellarray is pre-loaded with a plurality of beads. In some embodiments, themethod further comprises lysing at least one of the cells, therebyreleasing an RNA from the cell. In some embodiments, the methodcomprises capturing the RNA on a bead resident in the same microwell asat least one of the cells. In some embodiments, the method comprisescapturing said RNA on a bead resident in the same microwell as saidlysed cell. In some embodiments, the method further comprises removingthe membrane assembly from the microwell array. In some embodiments, themethod comprises collecting at least a portion of the plurality ofbeads. In some embodiments, the method comprises building a DNA or RNAlibrary of said bioparticles. In some embodiments, the method comprisesplacing two or more of said cellular cassettes onto a cassette frame. Insome embodiments, the method comprises releasing said plunger assembliesof the two or more cassettes on the cassette frame concurrently. In someembodiments, the method comprises collecting at least one bioparticlefrom each of the two or more cassettes on the cassette frameconcurrently.

Additional aspects and advantages of the present disclosure will becomereadily apparent to those skilled in this art from the followingdetailed description, wherein only illustrative embodiments of thepresent disclosure are shown and described. As will be realized, thepresent disclosure is capable of other and different embodiments, andits several details are capable of modifications in various obviousrespects, all without departing from the disclosure. Accordingly, thedrawings and description are to be regarded as illustrative in nature,and not as restrictive.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of exemplary embodiments are set forth withparticularity in the appended claims. A better understanding of thefeatures and advantages will be obtained by reference to the followingdetailed description that sets forth illustrative embodiments, in whichexemplary embodiments are utilized, and the accompanying drawings ofwhich:

FIGS. 1A-1B show an embodiment of the loading assembly. FIG. 1A shows aperspective view of a loading assembly with a loading ring attached,illustrating the loading assembly, the loading ring, the microwellarray, the base of the loading assembly, the snap clips, and the portfor fluid collection. FIG. 1B shows an exploded view of a loadingassembly, illustrating the loading assembly, the loading ring, themicrowell array, the base, the snap clips, a key hole, and the port forfluid collection.

FIGS. 2A-2B illustrate a perspective view of an embodiment of theloading assembly with an injection lid attached. FIG. 2A shows aperspective view of a loading assembly, illustrating the loadingassembly, the base of the loading assembly, the snap clips, the port forfluid collection, the injection lid, and a cutout on the injection lidfor guiding pipetting. FIG. 2B shows a perspective view of the injectionlid with a cutout for guiding pipetting.

FIG. 3A shows a top view of a microwell array with cutout holes; FIG. 3Billustrates a cross section of a portion of a microwell array,illustrating 3 individual microwells.

FIGS. 4A-4B show a perspective view of a plunger and a membraneassembly. FIG. 4A shows a perspective view of a membrane assemblyattached to the plunger assembly, illustrating the membrane assembly,the plunger assembly, the snap top, the snap clips, the membrane, themembrane frame, and the membrane bottom surface. The plunger is notshown in FIG. 4A. FIG. 4B shows a perspective view of a membraneassembly and a plunger assembly, unattached to each other, illustratingthe membrane assembly, the plunger assembly, the snap top, the snapclips, the plunger, the plunger bottom surface, the plunger sidesurface, the membrane, the membrane frame, and the membrane bottomsurface.

FIG. 5 shows a perspective view of a fully snapped device, illustratingthe snapped cassette, the port for fluid collection, the base of theloading assembly, and the top surface of the plunger assembly includinga handle, a concave surface, and openings for the keys.

FIG. 6 shows a perspective view of the cassette system that comprisessix fully snapped cassettes being inserted onto a Society forBiomolecular Screening (SBS) frame. The SBS frame, the keys on the SBSframe, the snapped cassettes, the base of the loading assembly, the snapclips, and the top surface of the plunger assembly including a handle, aconcave surface, and openings for the keys are illustrated. Multipleappearances of the same components are only labeled once in FIG. 6.

FIG. 7 shows a perspective view of opened cassettes on a SBS frame withmembrane assembly attached. The SBS frame, the keys on the SBS frame,the loading assembly, the base of the loading assembly, the snap clips,the membrane, the top surface of the membrane, and the membrane frameare illustrated. Multiple appearances of the same components are onlylabeled once in FIG. 7.

FIG. 8 shows a perspective view of opened cassettes on a SBS frame withmembrane assembly removed, illustrating the SBS frame, the keys on theSBS frame, the loading assembly, the base of the loading assembly, thesnap clips, and the microarray. Multiple appearances of the samecomponents are only labeled once in FIG. 8.

FIG. 9 shows a perspective view of the cassette system that comprisesconically shaped collection devices attached to the arrays. The SBSframe, the keys on the SBS frame, the loading assembly, the base of theloading assembly, the snap clips, and the collection devices with anopening on the conically shaped top surface are illustrated. Multipleappearances of the same components are only labeled once in FIG. 9.

FIGS. 10A-10C illustrate a schematic describing an exemplary protocolincluding array wetting (FIG. 10A), sample loading (FIG. 10B), cellfixing (FIG. 10C), and alternative procedures.

FIGS. 11A-11C illustrate an exemplary protocol including unsnapping aloading ring (FIG. 11A), snapping in a membrane/plunger (FIG. 11B), andaspirating excess storage buffer (FIG. 11C). The loading ring is notshown in FIG. 11A, and the membrane assembly is not shown in FIG. 11B.

FIGS. 12A-12C illustrate a perspective view of an embodiment of acassette. FIG. 12A shows a plunger assembly; FIG. 12B shows a membraneassembly; and FIG. 12C shows a loading assembly.

DETAILED DESCRIPTION Definitions

Unless defined otherwise, all technical and scientific terms used hereinhave the same meaning as is commonly understood by one of ordinary skillin the art.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting. As used herein, thesingular forms “a”, “an” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise.Furthermore, to the extent that the terms “including”, “includes”,“having”, “has”, “with”, or variants thereof as used herein mean“comprising”.

The term “about” or “approximately” can mean within an acceptable errorrange for the particular value as determined by one of ordinary skill inthe art, which will depend in part on how the value is measured ordetermined, i.e., the limitations of the measurement system. Forexample, “about” can mean within 1 or more than 1 standard deviation,per the practice in the art. Alternatively, “about” can mean a range ofup to 20%, up to 10%, up to 5%, or up to 1% of a given value.Alternatively, particularly with respect to biological systems orprocesses, the term can mean within an order of magnitude, within5-fold, and more preferably within 2-fold, of a value. Where particularvalues are described in the application and claims, unless otherwisestated the term “about” meaning within an acceptable error range for theparticular value should be assumed. For example, the amount “about 10”includes amounts from 8 to 12.

The term “substantially” as used herein can refer to a value approaching100% of a given value. In some embodiments, the term can refer to anamount that may be at least about 90%, 91%, 92%, 93%, 94%, 95%, 96%,97%, 98%, 99%, 99.9%, or 99.99% of a total amount. In some embodiments,the term can refer to an amount that may be about 100% of a totalamount.

Cellular Cassette

Disclosed herein are cellular cassette devices, systems, and kits forthe collection, storage, and/or analysis of biological samples andmethods of using the same. In some embodiments, disclosed herein arecassettes for collecting, storing, or analyzing bioparticles. Thecassette (e.g., cassette 1000 described herein) can comprise a plungerassembly, a membrane assembly, a loading assembly, or any combinationthereof. The cassette can comprise a plunger assembly, a membraneassembly, and a loading assembly. The cassette can comprise a membranesuch as a semi-permeable membrane and a loading assembly. The cassettecan comprise a membrane such as a semi-permeable membrane and amicrowell array.

In some cases, a cassette can further comprise a locking mechanism. Insome cases, the locking mechanism is configured to lock a plunger and amembrane assembly in place with a loading assembly. In some cases, thelocking mechanism is configured to lock a membrane assembly in placewith a loading assembly. The locking mechanism can take any suitableform, for example, mechanical, magnetic, and chemical. In someembodiments, the locking mechanism utilizes a mechanical means, such asa snap trap. In some embodiments, the locking mechanism utilizesmagnetic force. In some embodiments, the locking mechanism utilizesadhesives. In some embodiments, the locking mechanism comprises threadson one or more locking members. In the locking mechanism comprisesfriction fit. In some embodiments, the locking mechanism utilizes acassette clamp or other devices that operates to hold the various partsof the cassettes together. Accordingly, the cassette can be in a lockedformat or in an unlocked format. In some embodiments, the lockingmechanism is reversible, i.e., the lock can be engaged or disengagedreversibly. In other embodiments, the locking mechanism is irreversible.

A locking mechanism described herein can comprise one or more lockingmembers. In some embodiments, the locking mechanism comprises a toplocking member and a bottom locking member. In some embodiments, thelocking mechanism comprises one or more top locking members and one ormore bottom locking members. In some embodiments, a plunger assemblycomprises a top locking member that functions to maintain the positionof the plunger assembly in place with the membrane assembly, the loadingassembly, or both. In some embodiments, a membrane assembly comprises atop locking member that functions to maintain the position of themembrane assembly in place with the loading assembly. In someembodiments, a membrane assembly comprises a bottom locking member thatfunctions to maintain the position of the membrane assembly in placewith the plunger assembly. In some embodiments, a loading assemblycomprises a bottom locking member that functions to maintain theposition of the loading assembly in place with the membrane assembly,the plunger assembly, or both.

In some embodiments, disclosed herein is a cassette for collecting,storing, or analyzing bioparticles, said cassette comprises: (a) aplunger that comprises a top surface and a bottom surface; (b) amembrane assembly that comprises: (i) a semi-permeable membrane thatcomprises a membrane top surface and a membrane bottom surface, and (ii)a membrane frame configured to attach to said plunger, wherein saidsemi-permeable membrane is attached to said membrane frame, and whereinsaid membrane assembly is configured to allow at least a portion of saidbottom surface of said plunger to be in contact with said membrane topsurface when said membrane frame is attached to said plunger; (c) aloading assembly that comprises a base and a microwell array, whereinsaid microwell array comprises a top surface and a plurality ofmicrowells, wherein said loading assembly is configured to allow atleast a portion of said top surface of said microwell array to be incontact with said membrane bottom surface, and wherein said contact iscapable of retaining one or more bioparticles in said microwell array.In some embodiments, disclosed herein is a cassette for collectingand/or analyzing bioparticles, said cassette comprises: (a) a plungerthat comprises a top surface, a bottom surface, and a top lockingmember; (b) a membrane assembly that comprises: (i) a semi-permeablemembrane that comprises a membrane top surface and a membrane bottomsurface, and (ii) a membrane frame configured to reversibly attach tosaid plunger, wherein said semi-permeable membrane is attached to saidmembrane frame, and wherein said membrane assembly is configured toallow at least a portion of said bottom surface of said plunger to be incontact with said membrane top surface when said membrane frame isattached to said plunger; (b) a loading assembly that comprises: (i) abase that comprises a bottom locking member and one or more ports, and(ii) a microwell array bonded to said base, wherein said microwell arraycomprises a top surface and a plurality of microwells, wherein saidbottom locking member is configured to engage with said top lockingmember, thereby maintaining a contact between at least a portion of saidmembrane bottom surface and at least a portion of said top surface ofsaid microwell array, and wherein said one or more ports are configuredto allow liquid removal when said top locking member is engaged withsaid bottom locking member.

The cellular cassette can have a variety of use mode. For example, thecassette can have a sample loading mode, where the microwells areexposed and sample can be loaded. For another example, the cassette canhave a storage and shipping mode, where the cassette is closed thusprotecting the samples within the cassette. The cassette can be storedand/or shipped individually or on an SBS frame, where multiple cassettesare stored and/or shipped together. The cassette can have a sampleprocessing mode, where the samples within the microwells can beprocessed. One exemplary embodiment of the processing mode isillustrated in FIG. 8, where the backside of the membrane is exposed andbuffers or reagents can be added to the sample. The cassette can have asample collection mode, where the bioparticles and/or beads can beaggregated. In some embodiments of the sample collection mode, themembrane is released from the microwells.

In some embodiments, the cassette comprises: a membrane assembly, aloading assembly that comprises a plurality of microwells, a pluralityof beads, and a plurality of cells, wherein at least 80%, 90%, 95%, 98%,or 99% of the cells are loaded in the microwells as a single cell. Insome embodiments, the cassette comprises: a membrane assembly, a loadingassembly that comprises a plurality of microwells, a plurality of beads,and a plurality of lysed cells. In some embodiments, the cassettecomprises: a membrane assembly, a loading assembly that comprises aplurality of microwells, and a plurality of beads, wherein at least someof the beads comprise captured RNA molecules. In some embodiments, thecaptured RNA molecules originate from the cell that is resident in thesame microwell as the bead. In some embodiments, at least a portion ofthe cells or beads are retained in the microwells by a membrane that isreversibly attached to the microwells.

A cassette described herein can take any external shapes. In someembodiments, the cassette has a cylinder shape. In some embodiments, thecassette has a cuboid shape. In some embodiments, the cassette has acube shape. In some embodiments, the cassette is square when viewed fromthe top.

Plunger Assembly

In some cases, a cassette comprises a plunger assembly that comprises aplunger. When attached the membrane assembly, the plunger can providesupport to the membrane and protect the membrane while it is beingapplied to the microwell array. The plunger can also provide pressurethat facilitates the bonding between the membrane of the membraneassembly and the microwell array. The plunger assembly can comprise atop surface. In some embodiments, the top surface of the plungerassembly (i.e., plunger top surface or plunger flange) is rigid. The topsurface of the plunger assembly can be substantially flat so as toenable the vertical stacking of two or more cassettes. In some cases,the top surface of the plunger assembly comprises a handle. The plungertop surface can be of any suitable shape; for example, it can comprise acircle, a square, a diamond, a rectangle, a hexagon, etc. In someembodiments, the plunger comprises a bottom surface (i.e., plungerbottom surface). In some embodiments, the plunger bottom surface isrigid. In some embodiments, the plunger bottom surface comprises anelastomeric surface. In some embodiments, the plunger bottom surface iselastomeric. In some cases, the bottom surface of the plunger issubstantially flat. In some cases, the bottom surface of the plungercomprises a curved surface. In some specific embodiments, the bottomsurface of the plunger comprises a convex surface. The plunger bottomsurface can be of any suitable shape; for example, it can comprise acircle, a square, a diamond, a rectangle, etc. In some cases, the bottomsurface of the plunger is circular or substantially circular. In someembodiments, the plunger comprises a side surface. In some embodiments,the plunger side surface comprises one or more cutouts. In someembodiments, the plunger side surface comprises cutouts in a verticalpattern, such as groves that runs vertically on the plunger.

The plunger can comprise a cylindrical shape. In some embodiments, theside of the cylinder-shaped part comprises one or more channels. Theplunger can further comprise external side surfaces. The external sidesurfaces can comprise at least a part of the side surfaces of thecassette. In some cases, a plunger assembly comprises a top lockingmember. The top locking member can comprise a substantially verticalmember that is configured to be snap-locked together with a bottomlocking member. In some embodiment, the plunger comprises 1, 2, 3, 4 ormore top locking members. In some embodiment, the plunger comprises twotop locking members on the opposite side of the plunger.

Membrane Assembly

In some cases, a cassette described herein comprises a membraneassembly. The membrane assembly can comprise a membrane and a membraneframe. The membrane assembly can comprise a membrane and a membraneapplicator that is not a membrane frame. The membrane assembly can beconfigured to attach to the loading assembly. In some cases, themembrane assembly is configured to reversibly attach to the loadingassembly. The membrane assembly can be configured to attach to theplunger. In some cases, the membrane assembly is configured toreversibly attach to the plunger. The membrane assembly can furthercomprise a locking mechanism that secures it to the plunger, to theloading assembly, or both. In some embodiments, the membrane assemblycomprises one or more top locking members. In some cases, the membraneassembly can comprise a substantially circular shape.

In some embodiments, the membrane is impermeable. In some embodiments,the membrane is semi-permeable. In some embodiments, a semi-permeablemembrane is an ultrafiltration membrane or filtration membrane. Themembrane can comprise a membrane top surface and a membrane bottomsurface. The membrane top surface and bottom surface can independentlycomprise e.g., a circular, a square, a rectangle, a hexagon shape, orany other suitable shape. In some embodiments, the membrane top surfacehas substantially the same shape and size as the plunger bottom surface.

A semi-permeable membrane described herein can be configured to allow anobject of interest to pass through the membrane or to retain an objectof interest. In some embodiments, the semi-permeable membrane isconfigured to retain one or more beads. In some embodiments, thesemi-permeable membrane is configured to retain one or morebioparticles. In some embodiments, the semi-permeable membrane isconfigured to retain a cell, a genome, a nucleic acid, a virus, anucleus, a protein, or a peptide. In some embodiments, thesemi-permeable membrane is configured to allow a genome, a nucleic acid,a virus, a nucleus, a protein, or a peptide to pass through themembrane. In some embodiments, the semi-permeable membrane comprises anaverage pore diameter of at least 1 nm, at least 10 nm, at least 20 nm,at least 30 nm, at least 40 nm, at least 50 nm, at least 75 nm, at least100 nm, at least 200 nm, at least 300 nm, at least 400 nm, at least 500nm, at least 600 nm, at least 700 nm, at least 800 nm, at least 900 nm,or at least 1000 nm. In some embodiments, the semi-permeable membranecomprises an average pore diameter of at most 20 nm, at most 30 nm, atmost 40 nm, at most 50 nm, at most 75 nm, at most 100 nm, at most 200nm, at most 300 nm, at most 400 nm, at most 500 nm, at most 600 nm, atmost 700 nm, at most 800 nm, at most 900 nm, at most 1 μm, at most 2 μm,at most 3 μm, at most 5 μm, or at most 10 μm. In some embodiments, thesemi-permeable membrane comprises an average pore diameter of from about1 nm to about 200 nm. In some embodiments, the semi-permeable membranecomprises an average pore diameter of from about 1 to 200 nm, 15 to 150nm, 25 to 100 nm, or 25 to 75 nm. In some embodiments, a semi-permeablemembrane described herein has an average pore size in a range of 0.001to 0.25 times a largest lateral dimension of a cell and/or bead. In someembodiments, the semi-permeable membrane has an average pore size in arange of 0.001 to 0.1 times a largest lateral dimension of a cell. Insome embodiments, the semi-permeable membrane comprises an average poresize in a range of 0.001 to 0.1 times a largest lateral dimension of abead. In some embodiments, the semi-permeable membrane comprises anaverage pore diameter in a range of 1 nm and 200 nm.

In some embodiments, at least a portion of the membrane bottom surfaceis functionalized. A functionalized surface can facilitate theattachment between the membrane bottom surface and the microwell array.A method of making and using functionalized surfaces and semi-permeablearray can be referred to in, e.g., US 2019/0144936A1, which is herebyincorporated by reference in its entirety. In some cases, the membranebottom surface comprises one or more reactive functional groups. In somecases, the reactive functional group can comprise an amine, anaminosilane, a thiosilane, a methacrylate silane, a poly(allylamine), amaleimide, a 2-iminothiolane, a functional group derived frompolyacrylic acid or bisepoxy-PEG, or a combination thereof. In someembodiments, the membrane bottom surface bears a charge.

In some embodiments, the back side of the membrane (i.e., top membranesurface) is accessible after the membrane assembly is attached to theloading assembly. Such access to the back side of the membrane can beprovided by any suitable means. For example, in some embodiments, theplunger is removable from the membrane assembly, thus exposing the backside of the membrane. For another example, in some embodiments, suchaccess is provided by an opening on the plunger top and/or bottomsurfaces.

In some embodiments, the membrane assembly comprises a membrane (e.g.,semi-permeable membrane) attached to the membrane frame. In someembodiments, the membrane is bonded to the membrane frame. In someembodiments, the membrane is reversibly attached to the membrane frame.The membrane frame can be rigid and it also can comprise elastomericmaterials or surfaces. In some cases, the cassette comprises a membraneframe configured to attach to the plunger. The membrane frame can bereversibly attached to the plunger. For example, in some embodiments,the membrane frame can be snapped onto the plunger. In some embodiments,the membrane assembly is pre-attached to the plunger.

The membrane assembly can be configured to allow at least a portion ofthe bottom surface of the plunger to be in contact with the membrane topsurface when the membrane assembly is attached to the plunger. In someembodiments, the contact between the plunger bottom surface and themembrane top surface provides support for the membrane while it is beingattached to the microwell array. In some cases, a membrane can attach toa rigid surface. In some cases, a surface can comprise a frame insteadof a full slide, wherein a frame can be permanently bonded to amembrane. In some cases, a frame or other surface can reversibly attachto a plunger to create a single piece to apply and provide force forsealing a membrane to an array. In some cases, a plunger can push on amembrane through a membrane frame or other surface, to which themembrane is attached. In some cases, the membrane frame or othersurface, to which the membrane is attached, is configured to enableaccess to a backside of a membrane while it is sealed against an arrayto enable addition and diffusion of lysis, hybridization and enzymaticreactions through a membrane into wells while a membrane is stillattached to a frame. In some cases, the membrane frame or other surface,to which the membrane is attached, can enable easy removal of a membranewhen bead access is necessary by pulling on a frame instead of trying tograb a flimsy membrane.

In some embodiments, a membrane assembly described herein contacts atleast a portion of the plunger (e.g., the bottom surface of the plunger)directly. In some embodiments, a membrane assembly described hereincontacts at least a portion of the plunger through a medium. In someembodiments, a membrane assembly described herein does not directlycontact the plunger when the membrane assembly is attached to theplunger. The plunger can provide support for the membrane through amedium. Accordingly, in some embodiments of a cassette described herein,the cassette comprises a medium between the plunger and the membrane.The medium can function as a fluid reservoir. In some embodiments, themedium comprises a sheet that comprises an absorbent material. Exemplaryadsorbent materials include, but are not limited to, paper (such asfilter paper and tissue paper), superabsorbent polymers (e.g.,polyacrylic acid, polyacrylamide, ethylene maleic anhydride copolymer,carboxymethylcellulose, polyvinyl alcohol, polyethylene oxide,polyacrylonitrile, polysaccharide, or a copolymer that comprises any ofthe above polymers), hydrogels, and porous materials such as sponge. Insome embodiments, the medium comprises a layer of paper orsuperabsorbent polymer. The medium can comprises a buffer or a solution,e.g., a cell preservation solution such as RNALater or vivoPHIX.

In some embodiments, a cassette described herein comprises a fluidreservoir between the plunger and the membrane. The fluid reservoir cancomprise a solution and an adsorbent material. The fluid reservoir canbe inserted between a semi-permeable membrane and a plunger when thesepieces are clicked together such that the solution in the reservoir canpermeate the pores of the membrane. The reservoir can take the form ofan absorbent material such as filter paper that can be saturated withthe desired solution. Upon application of the membrane and plungercomponent to the array, the solution contained in the reservoir diffusesthrough the membrane and mixes with the solution in the wells. A commonsolution that can be applied in this way is a cell preservation solutionsuch as RNALater or vivoPHIX. In some embodiments, the fluid reservoirhas a thickness of about 5 nm to about 5 mm. In some embodiments, thefluid reservoir has a thickness within a range of from about 1 nm, 5 nm,25 nm, 50 nm, or 100 nm to about 500 nm, about 1 μm, about 5 μm, about25 μm, about 50 μm, about 500 μm, or about 1 mm. In some embodiments,the fluid reservoir has a thickness of about 50 nm to about 500 nm,about 100 nm to about 1 μm, about 1 μm to about 100 μm, about 50 μm toabout 500 μm, or about 100 μm to about 1 mm.

Loading Assembly

A cassette described herein can comprise a loading assembly. In someembodiments, the loading assembly comprises a microwell array. In someembodiments, the loading assembly comprises a microwell. In someembodiments, the loading assembly comprises a base, to which themicrowell array is attached to. In some cases, a cassette comprises aloading assembly that comprises a base and a microwell array. In someembodiments, the loading assembly can be configured to allow at least aportion of the top surface of the microwell array to be in contact witha membrane bottom surface. The contact between the microwell array andthe membrane bottom surface can seal the contacted portion of themicrowells and thus is capable of retaining one or more bioparticles inthe microwell array.

A microwell array (or array) can comprise a plurality of microwells (orwells). In some cases, the microwell array comprises from about 1000 toabout 1,000,000 microwells. In some cases, the microwell array comprisesfrom about 5000 to about 1,000,000 microwells. In some cases, themicrowell array comprises from about 50,000 to about 150,000 microwells.In some specific embodiments, the microwell array comprises about50,000, about 55,000, about 60,000, about 65,000, about 70,000, about75,000, about 80,000, about 85,000, about 90,000, about 95,000, about100,000, about 105,000, about 110,000, about 115,000, about 120,0000,about 130,000, about 140,000, or about 50,000 microwells. In someembodiments, a microwell array comprise one or more microwells. Themicrowells can be arranged in any pattern. In some embodiments, themicrowells are arranged in a hexagonal pattern.

A microwell can have a volume in the picoliter range, including volumesranging from less than 1 picoliter to about 10,000 picoliters. The rangecan be from about 1 picoliter to about 1000 picoliters, or about 5picoliters to about 1000 picoliters, or about 10 picoliters to about 500picoliters, or about 50 picoliters to about 125 picoliters. A microwellcan have dimensions (e.g., x and y or diameter, and height dimensions)in the micron ranges. For example, a microwell can have dimensions ofabout 45 microns (x) by about 45 microns (y) by about 60 microns (h) andhave a rectangular volume, or they may have dimensions of about 50microns (x) by about 50 microns (y) by about 50 (h) microns and have acube volume. The microwell can have cross-sectional area (from atop-down perspective) that is square, hexagon, circular, oval, etc.

A microwell array described herein can comprise a top surface, where theopenings of the microwells are located. In some embodiments, the topsurface of a microwell array comprises microwells displaced therein. Insome embodiments, an average diameter of the microwells on the topsurface is at most 1000 microns, at most 500 microns, at most 400microns, at most 300 microns, at most 200 microns, at most 100 microns,at most 75 microns, at most 50 microns, at most 40 microns, at most 30microns, at most 20 microns, at most 10 microns, or at most 5 microns.In some embodiments, an average diameter of the microwells on the topsurface is at least 5 microns, at least 7 microns, at least 10 microns,at least 20 microns, at least 30 microns, at least 45 microns, at least50 microns, or at least 100 microns. In some embodiments, an averagediameter of the microwells on the top surface is from about 5 microns toabout 50 microns. In some embodiments, a microwell is configured to holdan object of interest, e.g., a bead, a cell, a fragment of a tissue,etc.

A microwell array described herein can comprise a bottom surface. Insome embodiments, the bottom surface is impermeable. In someembodiments, the bottom surface is permeable or semi-permeable. In someembodiments, the bottom surface of the microwell array comprises asemi-permeable membrane. A semi-permeable bottom surface allows asolution to diffuse to the wells through the bottom of the array. Insome embodiments, a microwell array comprises an impermeable bottomsurface and the membrane of the membrane assembly is permeable orsemi-permeable, which allows a solution to diffuse from the top of themicrowell array. In some embodiments, a microwell array comprises asemi-permeable bottom surface and the membrane of the membrane assemblyis impermeable, which allows a solution to diffuse from the bottom ofthe microwell array. In some embodiments, a microwell array comprises asemi-permeable bottom surface and the membrane of the membrane assemblyis also semi-permeable, which allows a solution to diffuse from the topand the bottom of the microwell array. In some embodiments, a microwellarray comprises an impermeable bottom surface and the membrane of themembrane assembly is also impermeable, which substantially prevents asolution from diffusing out of the microwell array. In some embodiments,the membrane of the membrane assembly, or a portion thereof, is bondedto the top surface of the microwell array.

The microwells can comprise any suitable shape and geometry; forexample, they can be cylindrical, cuboid, conical, etc. In some cases,the microwells comprise a uniform depth in a range of 5 microns to 500microns. In some cases, the microwells are cylindrical and have auniform diameter in a range of 1 micron to 500 microns (e.g., 15-100microns or 1-10 microns). In some cases, the microwells are cuboid andhave a uniform largest lateral length in a range of 1 micron-500 microns(e.g., 15-100 microns or 1-10 microns). In some cases, the microwellsare conical and have a uniform diameter in a range of 35 microns to 100microns at a top surface and can have a uniform diameter in a range of0.5 microns to 3 microns at a bottom surface. In some cases, themicrowells have a uniform depth in a range of 30 microns to 100 microns.In some cases, the microwells have a largest lateral dimension in arange of 1 to 6 times that of the largest lateral dimension of a celland/or a bead. In some cases, the microwells have a largest lateraldimension in a range of 1 to 6 times the largest lateral dimension of acell. In some cases, the microwells have a largest lateral dimension ina range of 1 to 6 times the largest lateral dimension of a bead. In somecases, a total lateral area of microwells at the top surface of themicrowell array can comprise at least 10% of the total lateral area ofthe array. In some cases, the microwells have a uniform diameter in arange of 1 micron to 10 microns. In some cases, the microwells have auniform diameter in a range of 15 microns to 100 microns. In some cases,each of the microwells can comprise one or more cells.

In some embodiments, the microwell array comprises spatial barcodes. Thespatial barcodes can be located inside the microwells such as on aninterior surface of the microwells or on a bead that is resident in themicrowells. In some embodiments, each of the spatial barcodes is unique.In some embodiments, the array comprises unique spatial barcodes thatare unique to each of the microwells or to each cluster of microwells.In some embodiments, the location of each spatial barcode in themicrowell array is known. In some embodiments, the spatial barcodes arelocated at the bottom surfaces of the microwells.

The interior surface of the microwells can be functionalized. In someembodiments, each microwell comprises a functionalized surface thatcomprises one or more nucleic acid molecules having a unique spatialbarcode. In some embodiments, each unique spatial barcode is unique toone or a cluster of wells. In some embodiments, each well contains aunique combination of spatial barcodes. In some embodiments, each uniquespatial barcode is co-delivered with a unique stimulus. In someembodiments, the location of each spatial barcode on the array of wellsis known.

The microwell array can comprise one or more cutouts. The one or morecutouts can be used to direct pipetting. The one or more cutouts can beused to recover the beads, e.g., from the collection device. The one ormore cut-outs can be independently located anywhere on the array. Insome cases, a microwell array described herein comprises a cutoutlocated at the center of an array. In some cases, a microwell arraydescribed herein comprises a cutout located on the side of the array. Insome cases, a microwell array described herein comprises a cutoutlocated at the center of the array and a cutout located on the side ofthe array.

The top surface of a herein-described microwell array can befunctionalized. In some embodiments, the top surface of the microwellarray comprises one or more functional groups such as reactivefunctional groups. In some embodiments, the reactive functional groupscomprise an amine, an aminosilane, a thiosilane, a methacrylate silane,a poly(allylamine), poly(lysine), BSA, epoxide silane, chitosan,2-iminothiolane, a functional group derived from polyacrylic acid,bisepoxy-PEG, or oxidized agarose, or a combination thereof. Themicrowell array can comprise glass or a polymer material, for example,poly-dimethylsiloxane (PDMS), polycarbonate (PC), polystyrene (PS),polymethyl-methacrylate (PMMA), PVDF, polyvinylchloride (PVC),polypropylene (PP), cyclic olefin co-polymer (COC), and silicon. In someembodiments, the top surface of the array comprises functional groupsconjugated to cyclic olefin co-polymer using aryl diazonium salts. Insome embodiments, the top surface of the array bears a charge. In someembodiments, the top surface of the array bears a charge that isopposite to the charge bore on the membrane bottom surface.

The top surface of a herein-described microwell array can be bonded withthe membrane bottom surface, thereby substantially isolating at least aportion of the microwells. In some embodiments, at least 80%, at least85%, at least 90%, at least 95%, at least 99%, or at least 99.9% of thetop surface of the microwells is bonded with the membrane, therebysealing the microwells under the bonded membrane. In some embodiments,at least 80%, at least 85%, at least 90%, at least 95%, at least 99%, orat least 99.9% of the microwells is sealed with the membrane. A personskilled in the art would appreciate that in the case of a permeable orsemi-permeable membrane, objects that are able to pass through themembrane can diffuse or otherwise leave the sealed microwell through themembrane side.

The bonding between the top surface of the microwell array and themembrane bottom surface can be provided by physical or chemical force.For example, the bonding can be achieved by applying pressure, such asthrough a clamp. In some embodiments, the bonding is provided by amolecular bonding, such as through a chemical reaction of the functionalgroups. For example, the functional groups on the top surface of thearray and the functional groups on the membrane bottom surface can reactand thus bond with each other. A certain amount of pressure can berequired to form the molecule bonding. In some embodiments, the pressureprovided by the locking mechanism (e.g., the engagement between the toplocking member(s) and the bottom locking member(s)) is sufficient toprovide the pressure for molecule bonding. A period of time of contactcan be necessary to form the molecule bonding. In some embodiments, theperiod of time required to form the molecular bonding is at least 5seconds, at least 30 seconds, at least 1 minute, at least 5 minutes, atleast 10 minutes, at least 15 minutes, at least 20 minutes, at least 30minutes, at least 45 minutes, or at least 1 hour. In some embodiments,the period of time required is at most 2 hours, at most 1 hour, at most45 minutes, at most 30 minutes, at most 15 minutes, at most 10 minutes,at most 5 minutes, or at most 1 minute. In some embodiments, the periodof time required to form the molecular bonding is about 1 minute toabout 30 minutes. In some embodiments, the period of time required toform the molecular bonding is about 2 minute to about 15 minutes. Insome embodiments, the formation of the bonding between the top surfaceof the microwell array and the membrane bottom surface requires heating.For example, in some embodiments, the bonding between the top surface ofthe microwell array and the membrane bottom surface is formed at about30° C., about 40° C., about 50° C., about 60° C., or about 75° C. orabove. In some embodiments, the formation of the bonding between the topsurface of the microwell array and the membrane bottom surface does notrequire heating.

A microwell array described herein can be situated on or in a base ofthe loading assembly. The microwell array can be bonded to the base, orit can be part of the base. In some embodiments, the microwell array isreversibly attached to the base. In some cases, the base is rigid. Insome cases, the base comprises a bottom locking member that can beconfigured to engage the top locking member. The base can comprise 1, 2,3, 4, or more bottom locking members. In some embodiments, the basecomprises two bottom locking members. In some embodiments, the twobottom locking members are situated on the opposing corners of the base.In some embodiments, the two bottom locking members are not located onthe same edge of the base. In some embodiments, the bottom lockingmember is substantially vertical. The bottom locking member can beconfigured to engage a top locking member through a snap trap mechanism.In some cases, the contact between the microwell array and the membranebottom surface can be maintained by engaging a top locking member and abottom locking member, e.g. a trap snap. The trap snap design canprevent the opening of the cassette without a key. The trap snap designcan also ensure cassettes and contained samples are safe for shippingand storage.

In some cases, the base comprises one or more key holes configured toallow the insertion of one or more keys. The insertion of the one ormore keys can disengage the locking mechanism, e.g., disengaging the toplocking member and the bottom locking member. In some cases, theinsertion of the keys releases the plunger assembly from the loadingassembly. In some cases, the insertion of the keys releases the plungerassembly from the loading assembly and the membrane assembly. In somecases, the insertion of the keys releases the plunger from the loadingassembly while leaving the membrane assembly attached to the loadingassembly. In some cases, the insertion of the keys releases the plungerfrom the loading assembly while leaving the membrane assembly attachedto the plunger assembly.

In some cases, the base comprises a recessed area relative to themicrowell array (e.g., the recessed area 1133 described herein). Therecessed area can be used to accommodate excess fluid, e.g., the fluidretained by a loading ring. In some cases, the base comprises one ormore ports configured to allow liquid removal. In some embodiments, thebase comprises 1, 2, 3, 4 or more ports configured for fluid collection.In some embodiments, the base comprises one port. The one or more portscan be located in any suitable location of the base. For example, theexcess fluid can be pipetted away through the one or more ports. In somecases, the base comprises one port. In some cases, the one or more portsare situated on the side of the base. In some cases, the one or moreports are situated at the bottom of the base. In some cases, the basefurther comprises one or more channels that are capable of facilitatinga fluid flow from the recessed area to the one or more ports.

The loading assembly can comprise an elevated loading ring surroundingthe microwell array surface area. The loading ring can function toretain excess fluid on the microwell array. In some cases, the loadingring is configured to retain fluid on the microwell array. For example,the loading ring can be configured to retain from about 0.1 ml to about5 ml fluids. In some embodiments, the loading ring is configured toretain from about 0.25 to about 2 ml fluid, from about 0.5 to 1.5 mlfluid, or from about 0.75 to about 1.25 ml fluid. In some embodiments,the loading ring is configured to retain about 1 ml fluid. In somecases, the loading ring comprises a hydrophobic inward-facing surface.In some embodiments, the loading ring is hydrophobic. The hydrophobicring (or surface) can hold bulk sample solution over an array area withminimal meniscus to ensure uniform loading of bioparticles across thearray.

In some cases, the loading ring is part of the base. In some cases, theloading ring can be reversibly attachable to the base. The reversiblyattachable loading ring can have the same geometry as the membraneframe. In some embodiments, the loading has substantially the sameconfiguration as the membrane frame.

A loading assembly described herein can comprise an injection lid thatcovers at least a portion of the microwell array. In some embodiments,the injection lid covers at least 25%, 50%, 75%, 80%, 60%, 90%, 95%,99%, or 100% of the microwell array. In some embodiments, the injectionlid fully covers the microwell array. In some embodiments, the injectionlid does not fully cover the microwell array. In some embodiments, aloading assembly comprises either an injection lid or a loading ring. Insome embodiments, a loading assembly comprises an injection lid but nota loading ring. In some embodiments, a loading assembly comprises aloading ring but not an injection lid. In some embodiments, the loadingassembly lacks an injection lid. In some cases, the loading ringcomprises an injection lid that covers the microwell array. The lid cancomprise one or more openings. The one or more openings on the lid canbe used to direct pipetting. In some embodiments, the lid is a flip toplip that attaches or is connected with the loading assembly. In someembodiments, the lid is a snap lid. In some embodiments, the lid fitsonto the loading assembly by friction. In some embodiments, the lid hasthreads that engage with thread on the loading ring.

Bioparticles and Beads

The microwell array can comprise a plurality of beads such as capturebeads. In some cases, one or more microwells of the array comprise asingle bead. In some cases, at least 80%, 85%, 90%, 95%, 99%, 99.9%, or100% of microwells in the array comprise a single bead. In someembodiments, less than 10%, 5%, 4%, 3%, 2%, or 1% of the microwellscomprise two or more beads. In some cases, beads are pre-loaded into themicrowells. In some cases, beads are loaded into the microwells beforeor after the bioparticles are loaded. In some embodiments, beads andbioparticles are loaded simultaneously. The microwell array can beconfigured to hold one or more beads. In some embodiments, each of themicrowells is configured to hold a single bead. The semi-permeablemembrane can be configured to retain the beads such that the beadscannot pass through the membrane pores. The size of the capture beadscan be dictated by the size of the microwells that are used. In someembodiments, the size of the bead will be chosen such that only one beadcan occupy a microwell at a single time. Alternatively, the dimensionsof the microwells can be chosen such that only one bead occupies amicrowell at a single time. In some embodiments, the capture beads havean average diameter that is about 1 μm, about 5 μm, about 10 μm, about15 μm, about 25 μm, about 30 μm, about 35 μm, about 40 μm, about 45 μm,about 50 μm, about 55 μm, about 60 μm, about 65 μm, about 70 μm, about75 μm, about 80 μm, about 90 μm, about 100 μm, about 110 μm, about 120μm, about 150 μm, or about 200 μm. In some embodiments, the beads arefrom about 10 μm-50 μm in diameter. In some embodiments, the beads areabout 35 microns in diameter. In some embodiments, the beads aremagnetic.

As described herein, a capture bead can comprise a bead having a captureoligonucleotide attached to its surface, which comprises a capturedomain, site or sequence for annealing to target nucleic acids such astarget transcripts. When the target nucleic acids are transcripts thenthe bead can be referred to as a “transcript-capture bead”. In someembodiments, the transcript capture bead has a poly(dT) capture sequencefor annealing to the poly(dA) tail of mRNA transcripts. In someembodiments, the capture oligonucleotide further comprises a barcode.The barcode can be used for labeling captured nucleic acids from asingle cell, including all or a portion of captured transcripts of asingle cell. In some embodiments, transcripts of a single cell arecaptured when the transcript capture bead and the single cell are placedin the same microwell and the cell is lysed. The barcode can be used tolabel nucleic acids from a single cell or a single microwell. Thebarcode can also be used to label nucleic acids from a plurality ofcells or a plurality of microwells. In some embodiments, a barcodeidentifies a nucleic acid or a set of nucleic acids as being associatedwith a particular spatial location and/or with a particular treatment.In some embodiments, a barcode identifies a nucleic acid or a set ofnucleic acids as being associated with exposure to a particularstimulus. In some embodiments, a barcode comprises 3, 4, 5, 6, 7, 8, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23 24, 25, 26, 27,28, 29, or 30 nucleotides. In some embodiments, a barcode comprises 3,4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, or 16 nucleotides. In someembodiments, the capture sequence comprises about 5, 6, 7, 8, 9, 10, 11,12, 13, 14, 15, 16, 17, 18, 19, 20, 25 or 30 nucleotides. In someembodiments, the capture oligonucleotide comprises about 10, 20, 30, 40,or 50 nucleotides.

A microwell array described herein can comprise one or morebioparticles. In some cases, one or more microwells of the arraycomprise a single bioparticle (e.g., a single cell or a single bead thatcomprises biomaterial). In some cases, at least 80%, 85%, 90%, 95%, 99%,99.9%, or 100% of microwells in the array comprise a single bioparticle.In some cases, at least 100, 500, 1000, 5000, or 10,000 microwells inthe array comprise a single bioparticle. In some cases, at least 500 or1000 microwells in the array comprise a single bioparticle. In someembodiments, less than 10%, 5%, 4%, 3%, 2%, or 1% of the microwellscomprise two or more bioparticles. In some embodiments, less than 1% ofthe microwells comprise two or more bioparticles. In some embodiments,less than 5% of the microwells comprise two or more bioparticles. Insome embodiments, less than 10,000, 5000, 1000, 500, 100, 50, 25 or 10microwells in the array comprise two or more bioparticles. In somespecific embodiments, less than 2%, 1.5%, 1%, 0.5%, or 0.1% of themicrowells comprise two or more bioparticles. The microwell array can beconfigured to hold one or more bioparticles. In some embodiments, eachof the microwells is configured to hold a single bioparticle. Thesemi-permeable membrane can be configured to retain the bioparticlessuch that the bioparticles cannot pass through the membrane pores.

A bioparticle can refer to a particle that comprises biologicalmaterials. For example, a bioparticle can refer to a cell or a capturebead that has an RNA attached to it. The one or more bioparticles cancomprise a cell, a genome, a nucleic acid, a virus, a nucleus, aprotein, or a peptide. In some cases, the bioparticles comprise one ormore cells. In some cases, the one or more cells comprise a bacteriacell, a plant cell, an animal cell, or a combination thereof. In somecases, the one or more cells comprise a mammalian cell. In someembodiments, the cells are bacterial cells. In some embodiments, thecells are eukaryotic cells. In some embodiments, the cells areprokaryotic cells. In some embodiments, the cells are murine cells. Insome embodiments, the cells are primate cells. In some embodiments, thecells are human cells. In some embodiments, the cells are tumor cells.The cells (or nucleic acid source) may be naturally occurring or it maybe non-naturally occurring. In some embodiments, the cells are healthycells. In some embodiments, the cells are diseased cells.

In some embodiments, the cells are mammalian cells. The mammalian cellscan comprise one or more blood cells such as white blood cell (e.g.,monocytes, lymphocytes, neutrophils, eosinophils, basophils, andmacrophages), red blood cell (erythrocytes), or platelet.

Cellular Cassette System

Disclosed herein are systems comprising one or more herein describedcassettes. The system can comprise a cassette frame configured to holdone or more cassettes. In some embodiments, the cassette frame is aSociety for Biomolecular Screening (SBS) standard-sized frame. Thesystem can further comprise one or more keys that are capable ofdisengaging the locking mechanism. In some embodiments, the keys arecapable of releasing the plunger from the loading assembly.

In some cases, a cassette frame (such as SBS frame) can be designed toload multiple cassettes to enable multiplex processing. In some cases,1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20,21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38,39, 40, 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56,57, 58, 59, 60, 61, 62, 63, 64, 65, 66, 67, 68, 69, 70, 71, 72, 73, 74,75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89, 90, 91, 92,93, 94, 95, 96, 97, 98, 99, or 100 cassettes can be loaded onto acassette frame. In some embodiments, a cassette frame is configured tohold six cassettes. In some embodiments, a cassette frame is configuredto hold twelve cassettes. In some embodiments, a cassette frame (such asSBS frame) comprises key holes that are configured to insert one or morekeys. In some cases, the one or more keys can be built into an SBSframe.

The system can comprise from 1 to about 300 cassettes. In some cases, asystem can comprise about 6, about 8, about 12, about 24, about 96, orabout 120 cassettes. In some cases, at least two of one or morecassettes can be pre-connected. In some cases, all the cassettes on aSBS frame are pre-connected. In some cases, arrays can be pre-connected.In some cases, arrays can be made as multi-array systems fitting astandard SBS frame size. In some cases, a cassette frame can be builtwith trap snap keys built in to enable opening of a cassette as acassette is loaded onto a cassette frame. In some cases, a key can alsoact as a snap to hold a cassette base to a cassette frame.

A key that disengages a locking mechanism of the described cassette canbe of any suitable shape. In some embodiments, the key has a crosssection that comprises a cross sign shape. In some embodiments, the keyhas a cross section that comprises a square, a hexagon, a slotted, atri-wing, or a T-shape.

In some cases, a system can comprise one or more bioparticle collectionunits. In some cases, a collection unit can comprise one or morecollection plates which can comprise a plurality of recesses. In somecases, a collection unit can comprise one or more conically-shapedcassette collectors. In some cases, a cassette collector can comprise ahole at the center that allows beads to pass through. In some cases, acassette collector is configured to collect the bioparticles and/orbeads from a single cassette. In some cases, a cassette collector isconfigured to collect the bioparticles and/or beads from multiplecassettes, e.g., all the cassettes on an SBS frame.

Cellular Cassette Kit

Also disclosed herein is a kit for collecting and/or analyzingbioparticles. In some cases, a kit comprises instructions for using thedescribed cassettes and systems. In some cases, a kit can comprise oneor more cassettes and one or more reagents. In some cases, one or morereagents can comprise a wetting solution, a wash fluid, a lysis buffer,a fixative, a tissue storage reagent, a storage buffer, a cell culturemedia, or a combination thereof. In some cases, a kit can comprise atleast 1 cassette base with microwell array, a plunger, a membrane framewith membrane bonded to it, and any combination thereof. In some cases,a kit can further comprise a membrane frame pre-snapped to a plunger, anextra empty membrane frame to act as a cell loading ring, a cellinjection lid to cover an array during cell loading, washing buffers,cell fixing solutions, an SBS plate with trap snap keys built in, andany combination thereof. In some cases a kit can comprise from about 1to about 300 cassettes. In some case a kit can comprise about 6, about8, about 12, about 24, about 96, or about 120 cassettes. The kit canfurther comprise instructions of using the kit or a component within thekit.

In some embodiments, the kit comprises a membrane applicator forapplying a semi-permeable membrane to the array. In some cases,attachment of a semi-permeable membrane to an array surface can achieveoptimal transcript capture. In some cases, a generalized form of anapplicator consists of a membrane attached to a rigid backing of glassor acrylic plastic through a reversible chemistry, for example ahydrophilic thin film. In some cases, a thin film can comprise a saltbridge. In some cases, a thin film can comprise a hydrophilic polymer,which can enable a thicker film to be achieved. In some cases, ahydrophilic thin film can comprise a hydrophilic polymer such aspolyacrylamide, poly(vinyl alcohol), agarose or alginate. In some cases,a reversible chemistry can comprise a disulfide bridge created by abiotin-streptavidin interaction which can be cleaved by a reducingagent. In some cases, a reversible chemistry can comprise aphotosensitive linkage. In some cases, a reversible chemistry cancomprise an enzymatically cleavable linkage.

In some cases, an applicator can solve a shipping problem as anactivated membrane can be stable for extended periods adhered to a rigidbacking in a dry state, which can enable shipping membranes in standardmicroscope slide containers. In some cases, a scalable production ofindividual membranes can enable use of a clear acrylic support and athicker polymeric thin film. In some cases, using these materials,large, bulk applicators can be constructed. In some cases, acrylicbacking can enable laser cutting of a bulk applicator into 100s ofindividual applicators. In some cases, thicker thin film can be requiredto prevent fusion of a membrane to an acrylic backing during lasercutting, In some cases, enabling detachment of a membrane duringapplication. In some cases, an applicator can simplify attachment of amembrane to an array, as an entire applicator can be placed on top of anarray as a single dry piece. In some cases, following clamping andincubation, an applicator:array sandwich can be submerged in a solution.In some cases, a hydrophilic thin film can absorb water, In some cases,releasing a membrane from an applicator and leaving a membrane attachedto an array. In some cases, an applicator can negate a need for an enduser to handle a flimsy membrane and perform an error-prone membraneattachment procedure. In some cases, a membrane applicator can be 20,21, 22, 23, 24, 25, 26, 27, 28, 29, or 30 mm wide. In some cases, amembrane applicator can be 70, 71, 72, 73, 74, 75, 76, 77, 78, 79, or 80mm long. In other cases, a membrane applicator can be much largerincluding for example 1-5 feet by 1-5 feet (e.g., 2 feet×2 feet, or 2feet by 3 feet). In some cases, use of a larger applicator can enablesealing of a plurality of arrays simultaneously.

Also disclosed herein is a device comprising a membrane and a rigidsupport; wherein a membrane is attached to a rigid support through areversible chemistry. In some cases, the rigid support can compriseglass. In some cases, the rigid support can comprise acrylic plastic. Insome cases, the rigid support can comprise polycarbonate or polystyrene.In some cases, the rigid support can be about 1 to about 2 mm thick. Insome cases, a membrane can comprise a semi-permeable membrane. In somecases, a membrane can be plasma-activated. In some cases, a membrane cancomprise polycarbonate.

In some embodiments, the kit comprises a manual clamp. In some cases, aclamp comprises a three screw design. In some cases, a three screwdesign provides optimal pressure along a long axis of an array,preventing poor sealing at the ends of an array. In some cases, a squareclamp can completely encompass an array holder and top piece and onlytouch an array holder underneath an array causing an upward force to beunder an array. In some cases, a path can be allowed for fluid to leavean array surface. In some embodiments, the clamp is configured to applypressure on one or more, such as 6, 12, and 24, cassettes at the sametime.

In some embodiments, the kit comprises a crowding agent. A crowdingagent can function to increase nucleic acid capture efficiency. Thecrowding agent can be a zwitterionic or neutrally charged agent. In someembodiments, the crowding agent does not interfere with the chargeinteraction between the membrane and the array. A non-limiting exampleof a crowding agent is polyethylene glycol (PEG). In some embodiments,the PEG has a number average molecular weight of at least 1000 Da. Otherexemplary crowding agents include but are not limited to dextran,Ficoll, bovine serum albumin (BSA), and sucrose.

Methods of Use

Also disclosed herein is a method for collecting, storing, or analyzingbioparticles using a herein described cassette, system, or kit, or anycombination thereof. Also disclosed herein is a method for collecting,storing, or analyzing bioparticles using a cellular cassette.Accordingly, in some embodiments, the described method is for samplecollection. In some embodiments, the described method is for samplestorage. In some embodiments, the described method is for sampleprocessing. In some embodiments, described herein are cassettes,systems, and methods for asynchronous single-cell analysis. The methodscan be used to generate barcoded, single-cell sequencing libraries. Insome cases, a method can comprise: (a) loading a sample fluid thatcomprises one or more bioparticles onto a microwell array that can besituated on a base, wherein the microwell array can comprise a topsurface and a plurality of microwells, thereby loading a bioparticleinto at least one microwell; (b) applying a membrane assembly onto themicrowell array, wherein the membrane assembly can be attached to aplunger, and wherein the membrane assembly comprises a membrane frameand a semi-permeable membrane that comprises a membrane top surface anda membrane bottom surface; (c) and contacting at least a portion of thetop surface of the microwell array with at least a portion of themembrane bottom surface, and wherein the contact can retain at least onebioparticle in a microwell.

In some cases, the method can comprise attaching an elevated loadingring that surrounds a microwell array before a sample fluid is loaded.In some cases, the method can comprise wetting a microwell array beforea sample fluid is loaded. The wetting process can comprise loading awetting solution onto the microwell array. A suitable wetting solutioncan comprise, for example, alcohols such as ethanol, methanol, andpropanol, and surfactants. The wetting process can further compriseremoving the wetting solution from the microwell array. The wettingsolution can be removed by washing, drying, pipetting, etc. In someembodiments, the wetting process comprises washing the microwell arraywith a wash buffer (e.g., PBS 0.1% BSA). In some embodiments, thewetting process comprises loading a wash buffer onto the microwell arrayand leaving the buffer on the microwell array for about 30 minutes toabout 24 hours. In some embodiments, the wash buffer is left on thearray overnight. In some cases, the wetting process comprises removing awash buffer.

In some embodiments, the method comprises loading a sample fluid. Insome embodiments, the method comprises contacting the microwell arraywith a sample fluid. In some embodiments, the method comprisescontacting the microwell array with a tissue sample. The sample fluidcan be loaded manually or by automation. In some embodiments, the samplefluid is loaded by pipetting. In some embodiments, the sample fluid isloaded by flowing a sample solution over the loading assembly. Theloading of the sample fluid can be directed by the one or more cut-outsin the array, the opening(s) in the lid, or both. In some embodiments,the sample fluid is loaded to the cut-out area in the array. A suitablevolume of the loaded sample fluid can depend on various factors,including but not limited to, the size of the array, the number andvolume of the microwells in the array, the concentration of the samplefluid, etc. In some embodiments, the sample fluid comprises from about0.1 ml to about 5 ml liquid. In some specific embodiments, the samplefluid comprises about 0.2 ml, about 0.3 ml, about 0.4 ml, about 0.5 ml,about 0.6 ml, about 0.7 ml, about 0.8 ml, about 0.9 ml, about 1.0 ml,about 1.1 ml, about 1.2 ml, about 1.3 ml, about 1.4 ml, about 1.5 ml,about 1.6 ml, about 1.7 ml, about 1.8 ml, about 1.9 ml, or about 2.0 mlfluid.

The sample fluid can comprise one or more bioparticles. In someembodiments, the sample fluid comprises a plurality of bioparticles. Thebioparticles can exist in the sample fluid in various forms; forexample, the bioparticles can be dissolved in the sample fluid,suspended in the sample fluid, or in micelles that are distributed inthe sample fluid. In some specific embodiments, the sample fluidcomprises a suspension of cells.

In some embodiments, the ratio of the number of bioparticles in thesample fluid to the number of microwells in the microwell array can befrom about 1:1000 to about 10:1. In some cases, the ratio of the numberof bioparticles in the sample fluid to the number of microwells in themicrowell array can be from about 1:100 to about 1:1, from about 1:20 toabout 1:4, or from about 1:10 to about 1:8. In some cases, the ratio ofthe number of bioparticles in the sample fluid to the number ofmicrowells in the microwell array is from about 1:10 to about 1:8. Insome embodiments, at least 50%, at least 60%, at least 70%, at least80%, at least 90%, at least 91%, at least 92%, at least 93%, at least94%, at least 95%, at least 96%, at least 97%, at least 98%, or at least99% of bioparticles in the sample fluid are loaded in microwells. Insome embodiments, at least 95% of bioparticles in the sample fluid areloaded in microwells.

After the sample fluid is loaded, one or more of the microwells cancomprise one or bioparticles. In some embodiments, at least 0.5%, atleast 1%, at least 2%, at least 5%, at least 10%, at least 15%, at least20%, at least 30%, or at least 50% of the microwells comprise one ormore bioparticles. In some embodiments, at least 0.5%, at least 1%, atleast 2%, at least 5%, at least 10%, at least 15%, at least 20%, atleast 30%, or at least 50% of the microwells comprise a singlebioparticle. In some embodiments, from about 5% to about 20%, from about5% to about 15%, or from about 8% to about 12% of the microwellscomprise a single bioparticle. In some embodiments, the rest of themicrowells are not occupied by any bioparticles. In some embodiments,less than 10%, less than 5%, less than 2%, or less than 1% of themicrowells comprise two or more bioparticles.

In some embodiments, the method comprises mixing the loaded samplefluid. The mixing can be provided by agitating the loaded sample fluid,e.g., by pipetting one or more times. The mixing can be provided byswirling the loading assembly after the sample has been loaded. Themixing can also be provided by tilting the loading assembly. In someembodiments, the mixing comprises one or more means, such as agitatingand swirling. In some specific embodiments, the method comprisesagitating the loaded fluid by pipetting one or more times (such as 1-10times). In some embodiments, the sample fluid is agitated at a cut-outat the center of the array.

In some cases, the method can further comprise incubating a loadedsample fluid. The sample fluid can be incubated before the mixing, afterthe mixing, or both. In some embodiments, the sample fluid is incubatedstatically before the mixing (e.g., agitation). In some embodiments, thesample fluid is incubated statically after the mixing. The sample fluidcan be incubated for a period of time. In some embodiments, theincubation time is from about 30 seconds to about 12 hours, from about 1minute to about 1 hour, or from about 2 minutes to about 15 minutes, foreach incubation. In some embodiments, the incubation time is from about1 minute to about 10 minutes or from about 3 minutes to about 7 minutes.In some embodiments, the incubation time is about 5 minutes.

The method can comprise preserving the bioparticles after the samplefluid has been loaded. In some embodiments, the method comprisesapplying a storage buffer to the microwell array after a sample fluid isloaded. The storage buffer can operate to preserve the bioparticles orone or more biomaterials within the bioparticles. In some embodiments,the storage buffer operates to preserve polynucleic acids such as RNAsin the cells. The method can further comprise incubating thebioparticles in the presence of a storage buffer. In some cases, themethod can comprise removing the loading ring after a sample fluid isloaded. In some cases, the loading ring is removed after the storagebuffer has been loaded.

The method can comprise sealing at least a portion of the microwellswith the membrane. In some embodiments, the method comprises applyingthe membrane assembly onto the microwell array. The membrane assemblycan be applied using the plunger, to which it is attached. The membraneassembly can be applied using the membrane frame. In some embodiments,the membrane assembly is pre-assembled with the plunger, such that themembrane can be applied to the microwells by applying a downward forceon the plunger. In some embodiments, the plunger can be snapped into theloading assembly. In some embodiments, at least a fraction of thestanding fluid is displaced after the application of the membraneassembly. In some embodiments, the excess fluid on the microwell arrayis displaced after the membrane is applied. For example, the excessfluid can be displaced to the recessed area of the array. The displacedfluid can comprise a fraction of the sample fluid, a fraction of thewetting solution, a fraction of the wash buffer, a fraction of thestorage buffer, or a combination thereof. The displaced fluid can beremoved from one or more ports located on the side of the base. In someembodiments, a curved surface on the bottom surface of the plunger canfacilitate the displacement of excess fluid. In some cases, a curvedsurface of a plunger can enable robust liquid evacuation between amembrane and an array during plunger compression by providing a routefor fluid flow during depression. In some cases, a curved surface of aplunger can be critical for evacuation of a bulk liquid present on anarray during membrane attachment. In some embodiments, the displacedexcess fluid is removed, for example, through pipetting via the ports.

The method can comprise contacting at least a portion of the top surfaceof the microwell array with at least a portion of the membrane bottomsurface. In some embodiments, the contact can retain at least onebioparticle in a microwell. In some embodiments, the contact occurssimultaneously with the application of the membrane assembly onto themicrowells. In some embodiments, the contact occurs subsequently to theapplication of the membrane assembly. In some embodiments, at least 80%,at least 90%, at least 91%, at least 92%, at least 93%, at least 94%, atleast 95%, at least 96%, at least 97%, at least 98%, at least 99%, or atleast 99.9% of the microwells on the array are sealed by the membranethrough the contact. In some embodiments, at least 80%, at least 90%, atleast 91%, at least 92%, at least 93%, at least 94%, at least 95%, atleast 96%, at least 97%, at least 98%, at least 99%, or at least 99.9%of the top surface of the array is in contact with the membrane bottomsurface. In some embodiments, at least 80%, at least 90%, at least 91%,at least 92%, at least 93%, at least 94%, at least 95%, at least 96%, atleast 97%, at least 98%, at least 99%, or at least 99.9% of thebioparticles in the microwells are retained. A person skilled in the artcan appreciate that in the presence of a permeable or semi-permeablemembrane, the sealed microwells can be in fluidic communication with anyliquid outside of the microwells. A person skilled in the art can alsoappreciate that in the presence of a permeable or semi-permeablemembrane, objects, which are capable of passing through the membranepores, can enter and exit the microwells through the membrane.

In some embodiments, a molecular bonding is formed between the array topsurface and the membrane bottom surface after the contact. The molecularbonding can be formed after a period time of contact. The formation ofthe molecular bonding can also require pressure, temperature, or both.In some embodiments, the molecular bonding is formed at ambienttemperature or above. In some embodiments, the molecular bonding isformed after 1 minute, 2 minutes, 5 minutes, 10 minutes or more.

The methods can comprise storing at least one retained bioparticle forone or more days. The cassette or system that comprises the bioparticlecan also be placed into long term storage at a temperature below 0° C.,including for example at about −80° C. or at about −20° C. In someembodiments, a method described herein comprises storing a cassette orsystem that comprises a bioparticle at a temperature of about 40° C.,about 30° C., about 20° C., about 10° C., about 4° C., about 0° C.,about −10° C., about −20° C., about −30° C., about −40° C., about −50°C., about −60° C., about −70° C., or about −80° C. In some embodiments,the method comprises storing a cassette or system that comprises abioparticle at a temperature within a range of 0 to −20° C., 0 to −30°C., 0 to −50° C., 0 to −80° C., −20° C. to −80° C., or any rangestherebetween. In some embodiments, the method comprises storing acassette or system that comprises a bioparticle at ambient temperature.In some embodiments, the cassette or system that comprises one or morebioparticles is stored for a period of time that is between 1 hour and30 years, or any ranges therebetween. For example, the cassette orsystem can be stored for at least 1 day, at least 1 week, at least amonth, at least 2 months, at least 3 months, at least 4 months, at least5 months, at least 6 months, or at least a year. For example, thecassette or system can be stored for at most 1 day, at most 1 week, atmost a month, at most 2 months, at most 3 months, at most 4 months, atmost 5 months, at most 6 months, at most a year, at most 5 years, atmost 10 years, or at most 30 years. In some embodiments, a cassette orsystem described herein is stored for a period of 30 years or longer.The method can further comprise shipping the cassette or system thatcomprises one or more bioparticles. In some embodiments, the cassette orsystem is shipped from a point of care facility such as a clinic to acentral processing and/or analytical center.

The method can further comprise releasing the plunger from the membraneassembly, thereby exposing the membrane top surface. Alternatively, themethod can comprise other means of exposing the backside of the membrane(i.e., membrane top surface). After the membrane top surface is exposed,bioparticles retained in the microwells can be further processed. Insome embodiments, such processing comprises lysing the cells retained inthe microwells. In some embodiments, the method comprises contacting oneor more lysis buffers with the array. The method can comprise lysing atleast one cell, thereby releasing an RNA from the cell. The released RNAcan then be captured by a capture bead that is resident in the samemicrowell as the lysed cell. Accordingly, in some embodiments, themethod comprises capturing RNA on a bead resident in the same microwellas at least one cell. In some embodiments, other biomaterials releasedby the cell such as a DNA, an antibody, or a protein is captured by thecapture bead.

The beads can be pre-loaded into the microwells. In some cases, amicrowell array can be pre-loaded with a plurality of beads. In someembodiments, the beads are pre-loaded in a dry state. Alternatively, thebeads can be loaded before, after, or simultaneously as the samplefluid. In some embodiments, at least 80%, at least 90%, at least 91%, atleast 92%, at least 93%, at least 94%, at least 95%, at least 96%, atleast 97%, at least 98%, at least 99%, or at least 99.9% of themicrowells are loaded with a single bead. In some cases, the beads arebarcoded transcript capture beads. In some embodiment, depending on theapplication, one or more stimuli can be added to the microwells.

The method can comprise aggregating the one or more bioparticles in themicrowells. In some cases, the method comprises removing the membraneassembly from the microwell array, thereby exposing the sealedbioparticles. In some embodiments, the membrane frame is removed fromthe microwells. In some embodiments, the membrane is removed from themicrowells. The membrane can be removed by lifting the membrane frame.The membrane can also be removed by pealing or punching a hole in themembrane. In some cases, the method comprises collecting at least aportion of the bioparticles. In some cases, the method comprisescollecting at least a portion of the plurality of beads. Thebioparticles and/or beads can be aggregated using a bead collectiondevice. An exemplary bead collection device is illustrated in FIG. 8. Asillustrated in FIG. 8, the exemplary collection device has a conicalshape with a hole at the center configured for bead collection. In someembodiments, each bead collection device is configured to collect thebeads from a single cassette. In other embodiments, each bead collectiondevice is configured to collect the beads from two or more cassettes,e.g., all the cassettes on a SBS frame. In some embodiments, thebioparticles and/or beads are aggregated using a bead collection plate.

In some cases, a method can further comprise generating cDNA from acaptured RNA such that a sequence of a bead barcode can be incorporatedinto a cDNA. Provided herein is a method for spatially locatingtranscripts on the microwell array. The method can comprise contactingthe array with a plurality of cells containing one or more transcripts;generating cDNA from the transcripts on a barcoded capture bead suchthat the sequence of the unique bead barcode is incorporated into thecDNA. The unique spatial barcode can be simultaneously released from themicrowell surface, enabling binding of the spatial barcode to thebarcoded capture bead, thereby generating a fusion of the spatialbarcode and bead barcode. In some embodiments, the fusion is generatedby extending the bead capture probe through the hybridized spatialbarcode sequence during the reverse transcription reaction. In someembodiments, the location of the transcript on the array can be locatedby matching the bead barcode present in the cDNA molecule to a beadbarcode-spatial barcode fusion sequence in the sequencing data.

In some cases, automation can be used to perform these methods. It willbe appreciated that the same approach can be adopted for other nucleicacid sources that may be analyzed using the methods and products of thisdisclosure including without limitation viruses, nuclei, exosomes,platelets, etc.

In some embodiments, the cassettes, systems, and kits described hereinare functionalized to perform single-cell RNA-seq, e.g., as described inWO2017124101A2, U.S. patent application Ser. No. 16/213,551, and“Seq-Well: portable, low-cost RNA sequencing of single cells at highthroughput,” Nature Methods, 395 (14:4) 2017, which are herebyincorporated by reference in their entirety.

EXEMPLARY EMBODIMENTS Example 1. A Loading Assembly as Shown in FIGS.1A-1B

An exemplary loading assembly 1100, illustrated in FIGS. 1A-1B,comprises the microwell array 1120, the base of the loading assembly1130 that can support the microwell array, a locking mechanism such asthe snap clips 1131, the loading ring 1110, and the port for fluidcollection 1132. The base 1130 can comprise a recessed area 1133 that isconfigured to accommodate excess fluid. A key hole 1134 on the loadingassembly behind a snap clip 1131 is shown in FIG. 1B.

Example 2. A Loading Assembly

An exemplary loading assembly comprises a microwell array 1120, the baseof the loading assembly 1130, a locking mechanism such as the snap clips1131, the loading ring 1110, and the port for fluid collection 1132. Inthis embodiment, the port for fluid collection 1132 is located at thebottom of the base.

Example 3. A Loading Assembly as Shown in FIGS. 2A-2B

An exemplary loading assembly 1100, illustrated in FIGS. 2A-2B,comprises the injection lid 1111, the base of the loading assembly 1130,a locking mechanism such as the snap clips 1131, and the port for fluidcollection 1132, and a cutout on the injection lid for guiding pipetting1112. Although the cutout on the injection lid is shown in FIGS. 2A-2Bto be on the side of the lid, it can be situated in any position of thelid such as at the center of the lid.

Example 4. A Microarray as Shown in FIGS. 3A-3B

An exemplary microarray 1120 with cutouts 1121 is illustrated in FIG.3A. The cutouts can be used to recover capture beads from the collectiondevice at the end of the capture process.

A cross section of an exemplary microarray 1120 showing 3 individualmicrowells 1122 is illustrated in FIG. 3B (the rest of the microwells onthe array are not shown). Each of the microwells 1122 comprises anopening at the top 1123, a bottom surface 1124 and a side surface 1125.

Example 5. A Microarray with Optionally One Cutout

An exemplary microarray 1120 can have only one cutout 1121. The cutoutcan be used to guide the pipetting of samples or recover beads from thecollection device. The cutout can be situated anywhere on themicroarray. For example, a microarray can comprise a cutout at thecenter or on the side of the microarray. In some exemplary microarrays,the cutout is absent.

Example 6. A Plunger Assembly and a Membrane Assembly as Shown in FIGS.4A-4B

An exemplary plunger assembly 1200, illustrated in FIGS. 4A-4B,comprises a top surface (i.e., snap top) 1230, snap clips 1211 thatfunction to lock the plunger assembly in place with the loadingassembly, and a plunger 1220 that has a plunger bottom surface 1221 anda plunger side surface 1222 that has optional vertical groves on it.

An exemplary membrane assembly 1300, illustrated in FIGS. 4A-4B,comprises a membrane 1320 and a membrane frame 1310. The membranecomprises a membrane bottom surface 1321 and a membrane top surface (notshown in FIGS. 4A-4B).

The membrane assembly 1300 can be reversibly attached to the plungerassembly (FIG. 4A), and they can be detached (FIG. 4B).

The membrane assembly 1300 can optionally comprise a locking mechanism(not shown in FIG. 4A-4B), such as snap clips. One locking mechanism onthe membrane assembly can engage with a locking snap of the plungerassembly, thereby locking in place the membrane assembly with theplunger assembly. A second locking mechanism on the membrane assemblycan engage with a locking snap of the loading assembly, thereby lockingin place the membrane and plunger assembly with the loading assembly.The locking mechanism can operate mechanical (such as a snap trap), byfriction, or by any other suitable means.

Example 7. A Fully Snapped Cassette as Shown in FIG. 5

An exemplary fully snapped cassette 1000, illustrated in FIG. 5,comprises a plunger assembly 1200 at the top, a loading assembly 1100 atthe bottom, and additional interior components that are not shown (e.g.,a membrane assembly 1300). The snap top 1230 of the plunger assembly1200 is illustrated, which comprises on its top surface a handle 1231that can be used to open, close, or otherwise manipulate the cassette(e.g., detaching or attaching the plunger assembly to the loadingassembly), a concave surface area 1232 that is figured to allow theapplicator to conveniently access the handle, and one or more openings1233 that are part of a locking mechanism, which enables multiplecassettes to be opened on a SBS frame simultaneously and/orautomatically. The base of the loading assembly 1130, which comprises aport for fluid collection 1132, is also illustrated in FIG. 5.

Example 8. A Cassette System that Comprises Six Fully Snapped Cassettesas Shown in FIG. 6

An exemplary cassette system, illustrated in FIG. 6, comprises an SBSframe 2000 and six fully snapped cassettes 1000. The SBS frame 2000comprises multiple keys 2100 on the top side of its surface. The keys2100 protrude upward from the SBS frame 2000 and they have a crosssection that is shaped as a cross sign. As illustrated, when viewed fromthe side, the keys are narrower at the top and have a smaller crosssection at the tip to allow for easy insert into the cassettes. The keysand the snap clips on the cassettes are configured such that when thekeys are inserted into the corresponding slots on the cassettes, theplunger assembly will be detached from the loading and membraneassemblies (not shown).

Each of the cassettes 1000, illustrated in FIG. 6, comprises a plungerassembly 1200 at the top, a loading assembly 1100 at the bottom, andadditional interior components that are not shown (e.g., a membraneassembly 1300). The snap top 1230 of the plunger assembly 1200 isillustrated, which comprises on its top surface a handle 1231 that canbe used to open, close, or otherwise manipulate the cassette (e.g.,detaching or attaching the plunger assembly to the loading assembly), aconcave surface area 1232 that is figured to allow the applicator toconveniently access the handle, and one or more openings 1233 that arepart of a locking mechanism, which enables multiple cassettes to beopened on a SBS frame simultaneously and/or automatically. As shown inFIG. 6, the snap top has a flat top surface, enabling stacking of thecassettes and convenient storage. The base of the loading assembly 1130,which comprises snap clips 1131, is also illustrated.

Example 9. A Cassette System that Comprises Six Opened Cassettes on anSBS Frame as Shown in FIG. 7

An exemplary cassette system, illustrated in FIG. 7, comprises an SBSframe 2000 and six opened cassettes that each comprises a membraneassembly 1300 and a loading assembly 1100. The SBS frame 2000 comprisesmultiple keys 2100 on the top side of its surface. The keys 2100protrude upward from the SBS frame 2000 and they have a cross sectionthat is shaped as a cross sign. As illustrated, when viewed from theside, the keys are narrower at the top and have a smaller cross sectionat the tip to allow for easy insert into the cassettes. Upon theinsertion of the keys into the corresponding slots on the cassettes, theplunger assemblies (not shown) are detached from the loading assemblies.Each of the membrane assemblies 1300 comprises a membrane frame 1310 anda membrane 1320. The membrane has a membrane bottom surface (not shown)and a membrane top surface 1322. Each of the loading assemblies 1100comprises a base 1130, snap clips 1131, and additional components notshown in this figure (e.g., a microarray).

Example 10. A Cassette System that Comprises Six Opened Cassettes on anSBS Frame as Shown in FIG. 8

An exemplary cassette system, illustrated in FIG. 8, comprises an SBSframe 2000 and six opened cassettes that each comprises a loadingassembly 1100. The SBS frame 2000 comprises multiple keys 2100 on thetop side of its surface, which protrude upward from the SBS frame 2000.The keys 2100 are inserted into the key holes of the loading assembly.Each of the loading assemblies 1100 comprises a base 1130, snap clips1131, and microarray 1120.

Example 11. A Cassette System that Comprises Six Cassettes andCollection Devices on an SBS Frame as Shown in FIG. 9

An exemplary cassette system, illustrated in FIG. 9, comprises an SBSframe 2000 and six cassettes that each comprises a loading assembly 1100and a collection device 3000. The SBS frame 2000 comprises multiple keys2100 on the top side of its surface. The keys 2100 protrude upward fromthe SBS frame 2000. Each of the loading assemblies 1100 comprises a base1130, snap clips 1131, and additional components not shown in thisfigure (e.g., a microarray). Each of the collection devices 3000comprises a conically shaped top surface 3020 and an optional smallopening 3010 at the center of the top surface that is configured toallow beads to pass through when the cassette is inverted.

Example 12. Protocol of Use

An exemplary protocol of use can be seen in FIG. 10 and FIG. 11.

Array wetting (shown in FIG. 10A). 1 mL of methanol was added to wet themicroarray and allowed to incubate for 5 minutes. The microarray wasthen washed three times with PBS with 0.1% bovine serum albumin (BSA).Alternatively, 1 ml PBS 0.1% BSA; 1 hr-overnight; No washing.

Sample loading (shown in FIG. 10B). The wetting solution was thenremoved with a 1 ml pipette, and 1 ml of cell suspension was added andallowed to incubate statically for five minutes. The solution was thenagitated by pipetting three times and again allowed to incubate for fiveminutes. Alternatively, agitate by swirling.

Cell fixing (shown in FIG. 10C). The cells were fixed by washing twicewith PBS, followed by the addition of storage buffer, and ten minutes ofincubation (optional). Alternatively, no washes if cell loading solutionis low in protein.

Loading ring removal (shown in FIG. 11A). The loading ring wasunsnapped.

Snapping in membrane/plunger (shown in FIG. 11B). After the loading ringwas removed, the snap-in top with membrane assembly/plunger assembly wassnapped in. The liquid that is situated on the microarray can bedisplaced when the membrane assembly is attached to the loadingassembly. Ensure enough space around array to accommodate displacedliquid.

Removal of excess storage buffer (shown in FIG. 11C) (optional). Theexcess storage buffer was aspirated using a pipette. The microarray canbe tilted toward the port (or opening) for fluid collection to allow alldisplaced liquid to flow there for removal.

Example 13. Alternative Protocol

An exemplary alternative protocol can also be seen in FIG. 10 and FIG.11. 1 mL of PBS with 0.1% bovine serum albumin (BSA) was added to wetthe microarray and it was allowed to incubate from between 1 hour toovernight. The wetting solution was then removed with a 1 ml pipette,and 1 ml of cell suspension was added and allowed to incubate staticallyfor five minutes. The solution was then agitated by swirling and againallowed to incubate for five minutes. The cells were fixed by theaddition of storage buffer, and ten minutes of incubation. The loadingring was unsnapped, and the snap-in top with membrane assembly/plungerassembly was snapped in. The excess storage buffer was aspirated using apipette.

Example 14. A Cassette as Shown in FIGS. 12A-12C

An exemplary cassette that comprises a plunger assembly 1200, a membraneassembly 1300, and a loading assembly 1100 is shown in FIGS. 12A-12C.

An exemplary plunger assembly 1200, illustrated in FIG. 12A, comprises atop surface (i.e., snap top) 1230, snap clips 1211 that function to lockthe plunger assembly 1200 in place with the loading assembly 1100 and/orthe membrane assembly 1300, and a plunger 1220 that has a plunger bottomsurface (not shown) and a plunger side surface 1222. The plunger topsurface 1230 comprise key openings 1233.

An exemplary membrane assembly 1300, illustrated in FIG. 12B, comprisesa membrane (not shown) and a membrane frame 1310. The membrane framecomprises snap clips 1311 and finger grips 1312. The membrane assembly1300 can be reversibly attached to the plunger assembly 1200. Themembrane assembly 1300 can be reversibly attached to the loadingassembly 1100.

An exemplary loading assembly 1100, illustrated in FIG. 12C, comprisesthe microwell array 1120, the base of the loading assembly 1130 that cansupport the microwell array, and a locking mechanism such as the snapclips 1131. The base 1130 comprises a recessed area 1133 that isconfigured to accommodate excess fluid. The base 1130 comprises a keyhole 1134 that is configured to insert a key that can disengage alocking mechanism. The base 1130 can optionally comprise a port forfluid collection, which is not present in the exemplary loading assemblyof FIG. 12C.

The examples and embodiments described herein are for illustrativepurposes only and various modifications or changes suggested to personsskilled in the art are to be included within the spirit and purview ofthis application and scope of the appended claims.

1.-149. (canceled)
 150. A cassette for collecting, storing, or analyzingbioparticles, said cassette comprises: (a) a loading assembly thatcomprises a microwell array and a locking member, wherein said microwellarray comprises a plurality of microwells situated on a base and aplurality of beads; and (b) a loading ring reversibly attached to thebase, wherein the loading ring is configured to retain excess fluid onthe microwell array.
 151. The cassette of claim 150, wherein the loadingring is configured to retain from about 0.1 ml to about 5 ml fluid. 152.The cassette of claim 150, wherein the loading ring is configured toretain from about 0.5 to 1.5 ml fluid.
 153. The cassette of claim 150,wherein the loading assembly further comprises an injection lid thatcovers at least a portion of the microwell array.
 154. The cassette ofclaim 153, wherein the injection lid covers at least 80% of themicrowell array.
 155. The cassette of claim 153, wherein the injectionlid has an opening that is configured to direct pipetting.
 156. Thecassette of claim 150, wherein the microwell array comprises at least1000 microwells that each comprises a single cell.
 157. The cassette ofclaim 150, wherein the loading assembly further comprises a port forfluid collection.
 158. The cassette of claim 150, wherein the loadingassembly further comprises a key hole.
 159. The cassette of claim 150,wherein the microwell array comprises a wetting solution or a washbuffer.
 160. A method for collecting, storing, or analyzing bioparticlesusing a cellular cassette, wherein said cellular cassette comprises: (a)a loading assembly that comprises a microwell array and a lockingmember, wherein said microwell array comprises a plurality of microwellssituated on a base and a plurality of beads; and (b) a loading ringreversibly attached to the base, wherein the loading ring is configuredto retain excess fluid on the microwell array; wherein said methodcomprises (a) loading a sample fluid that comprises one or more cellsonto said microwell array, thereby loading at least one cell into one ofsaid microwells.
 161. The method of claim 160, further comprisingwetting the microwell array before the sample fluid is loaded.
 162. Themethod of claim 160, further comprising mixing the loaded sample fluid.163. The method of claim 160, further comprising incubating the loadedsample fluid from about 30 seconds to about 12 hours.
 164. The method ofclaim 160, further comprising applying a storage buffer to the microwellarray after the sample fluid is loaded, wherein the storage buffer isconfigured to preserve polynucleic acids.
 165. The method of claim 160,further comprising removing the loading ring after the sample fluid isloaded.
 166. The method of claim 165, further comprising applying amembrane assembly onto the loading assembly, wherein the membraneassembly comprises (a) a semi-permeable membrane that comprises amembrane top surface and a membrane bottom surface, and (b) a membraneframe configured to reversibly attach to said loading assembly, whereinsaid semi-permeable membrane is attached to said membrane frame. 167.The method of claim 166, wherein the membrane assembly is reversiblyattached to a plunger assembly that comprises a plunger, and whereinsaid plunger comprises a bottom surface.
 168. The method of claim 167,wherein the membrane assembly is pre-assembled with the plungerassembly.
 169. The method of claim 167, wherein the plunger assembly orthe membrane assembly comprises a top locking member that is configuredto engage with said locking member of the loading assembly.